The 1760 and 1784 eruptions of Wrangell are questionable, poorly documented, and may in fact refer to a volcano other than Mt. Wrangell. Dall (1870) says that "Chechitno" smoked in 1760, and again in July 1784.
These eruptions are first reported by Grewingk (1850, translated 2003 by Fritz Jaensch) as being from Chetchina, which he says is one of the Andreanof Islands. Petroff (1884), translating Grewingk, reports 1760 and 1784 eruptions from Chechina. Also derived from Grewingk, Dall (1870) and Becker (1898) report eruptions from Chechitno in 1760 and 1784. Becker (1898) states: "Mount Wrangell lies at a distance of about 134 miles from the head of Prince William Sound, and, according to Lieut. H. T. Allen, it reaches the great height of 17,500 feet. It was steaming at the date of his visit. It is the loftiest of a group of high mountains, one of which, named Mount Blackburn by Mr. Allen, is only 30 miles from the junction of the Copper River and the Tschichitna, Chechitna, or Chittyna River. I suppose this latter mountain to be that called by earlier writers the Chechitno volcano." Translation of Shmalev (found in Juergen Kienle's files) equates the Island of Chetkhina with Great Sitkin, which has historical accouts of eruptions in 1760 and 1784. According to the Smithsonian Institution Chechitno is a synonym of Wrangell. Additionally, according to Grewingk (1850, translated 2003 by Fritz Jaensch), Mt. Wrangell was not discovered until 1819.

The 1760 and 1784 eruptions of Wrangell are questionable, poorly documented, and may in fact refer to a volcano other than Mt. Wrangell. Dall (1870) says that "Chechitno" smoked in 1760, and erupted in July 1784.
These eruptions are first reported by Grewingk (1850, translated 2003 by Fritz Jaensch) as being from Chetchina, which he says is one of the Andreanof Islands. Petroff (1884), translating Grewingk, reports 1760 and 1784 eruptions from Chechina. Also derived from Grewingk, Dall (1870) and Becker (1898) report eruptions from Chechitno in 1760 and 1784. Becker (1898) states: "Mount Wrangell lies at a distance of about 134 miles from the head of Prince William Sound, and, according to Lieut. H. T. Allen, it reaches the great height of 17,500 feet. It was steaming at the date of his visit. It is the loftiest of a group of high mountains, one of which, named Mount Blackburn by Mr. Allen, is only 30 miles from the junction of the Copper River and the Tschichitna, Chechitna, or Chittyna River. I suppose this latter mountain to be that called by earlier writers the Chechitno volcano." Translation of Shmalev (found in Juergen Kienle's files) equates the Island of Chetkhina with Great Sitkin, which has reported eruptions in 1760 and 1784. According to the Smithsonian Institution Chechitno is a synonym of Wrangell. Additionally, according to Grewingk (1850, translated 2003 by Fritz Jaensch), Wrangell is not discovered until 1819.

Grewingk (1850, translated 2003 by Fritz Jaensch) writes that Klimovskii and Wrangell report that Wrangell volcano was discovered in 1819, "active, and several earthquakes annually."

The journal of John Bremner, a prospector who lived among the Copper River Indians, was found at Nuchuk in 1886 by Heywood Walter Seton-Karr, and published by Seton-Karr in Shores and alps of Alaska (1887) records an eruptive event at Mt. Wrangell. John Bremner's journal starts on September 1, 1884, but no metion is made of Wrangell until October 26: "Clear but verey cold the floor of my cabin is frose two foot from the fire and I thought I had made it almost air tight so you see I am in no danger of melting with the heat. I saw the Volcano smoking for the first time to-day it is the mountin laid down on the chart as Mt. Wrangle it dont look more than twenty-five or thirtey miles from here but the natives say it will take me three days to go thar I cant get one of them to go near it so I will have to go alone I sholl go as soon as the river is safe."
On February 3, 1885, Bremner describes a more robust eruption: "A beautifull day not a cloud in the sky I was treated to a sight to-day that I wish you could have seen the volcano has been verey quite (quiet) a good while but to-day it is sending out a vast column of smoke and hurling imense stones hundreds of feet high in the air the mases it is throwing up must be verey large to be seen here it is at least thirty milles in a air line from here to the mouth of the crater it has mde no loud reports onley a sort of rumbling noise."
He continues on February 4, 1885: "A little colder but pleasant the Volcano has stoped throwing stones ore making a noise but is still sending out an imense cloud of smoke it is verey beautifull not a breath of wind and the smoke ascends to a great hight in an imense colum before spreading out."
His next entry is not until February 5, which states that the weather is cloudy. The journal ends on February 7, with no further mentions of Wrangell.
Other reports of this eruption include: Becker (1898) recording that Wrangell "in eruption" in 1884, and Mendenhall (1903) reporting that Lieutenant Allen observed smoke from Wrangell in 1885. Although some steam from Wrangell in 1884/1885 seems probable, an eruption as robust as the one Bremner describes is questionable. It is doubtful that Bremner could have seen the sights he describes from a distance of ~30 miles.

AVO thanks LeEric Marvin for directing us to Seton-Karr's book.

Sapper (1917) reports a "silent eruption of fire" at Wrangell in 1890.

From Motyka (1983): "An eruption of Mount Wrangell, during the Icy Bay earthquake (magnitude 8.3) of September 4, 1899 was recorded by the chief quartermaster, and by the head guide of an expedition mapping the Copper Center region (Abercrombie, 1900). Both men claimed they saw an eruptive plume over the summit and lava flowing down the northwest flank immediately following the earthquake. Icy Bay is located 260 km southeast of Mount Wrangell." The guide, A.M. Powell, reported that Mount Wrangell steamed profusely just after a great earthquake and continued to 'smoke with unusual animation for the rest of the season' (Abercrombie, 1900)."
Miller and others (1998) write that "Photographs of the ash covered summit of Mt. Wrangell that appear in the reports of Mendenhall and Schrader (1903) and Mendenhall (1905) may reflect an increase in activity following the September 3, 1899 Yakutat earthquake."

An article in the June 10, 1902 edition of the Galveston Daily News states "In June, 1900, I observed a black patch several miles in extent on the southern slope of the mountain, extending from the summit down to perhaps 11,000 feet elevation. As it was covered with snow when the mountain was next seen, about the last of September, it seems probable that the bare area was due to material thrown out by the volcano." This report may not constitue a volcanic eruption, however, as a well-known fumarole patch on the southwestern flank of the volcano often appears as bare ground.
Richter and others (1995) report eruptive activity at Mt. Wrangell in 1900.

From Crosby (1907): "To the editor of Science: Mr. Arthur P. Porter, civil engineer and graduate of the Massachusetts Institute of Technology, writing from Elliott Creek, Alaska, under date of May 24, 1907, communicates the following interesting observations:
"On and about April 5, several mountains of the Wrangell range in Alaska were active volcanically, sending up great clouds of steam and causing a flood in the Kotsina River that, on April 6, came down past our camp at the mouth of the Kotsina, cut us off from our supply train and prevented our going up the Kotsina on the ice.
"To go more into detail, the first we heard about it was on April 1, when we were mushing down the Tonsino River. We stopped for dinner at the camp of some freighters hauling in supplies for the Hubbard-Elliott mine; and Mr. Hubbard said that they could plainly see the smoke (?) rising from Mt. Wrangell. That afternoon and the following day, as we proceeded down the Tonsino and then down the Copper River, we caught occasional distant views of the mountains, but I noted nothing remarkable. (A photograph taken April 2 shows the mountains clear.) On April 5 and 6 we saw great white clouds which always rolled away from the mountains, yet never left them clear; and with the field glasses steam was seen issuing from the sides of the mountains below the tops. We were at the mouth of the Kotsina, about forty miles from the mountains, and could not positively identify the peaks. Apparently, however, Mts. Wrangell, Blackburn, and Sanford were all sending up steam.
"The next day, April 6, a sudden flood came down the Kotsina on top of the ice and underneath it. There had been no warm weather and no rain (28 degrees below zero instead). The flood lasted two days and then went down. The enclosed photograph [not published] shows the head of the flood advancing down the river and spreading over the snow as it came. I stepped on an ice hummock to take the picture; and by the time I could focus my camera, the flood had passed me on both sides and nearly cut me off. The toe of the flood advanced at the rate of fifty feet a minute, actual timing, eating its way through the snow as if the water were warm.
"May 28, the mountains seem to be steaming again (Mt. Drum or Mt. Sanford), and others noted the same two days ago."

From Motyka (1983): "Mount Wrangell was climbed in July 1908 by R. Dunn and W. Soule. Dunn (1909) reported considerable venting of vapor from the depths of the West Crater with plumes rising from 2 to 3 km above the crater. All that was visible of the North Crater were the peaks located on the west rim, the remainder of the crater apparently being snow covered."

From Motyka (1983): "[T]he Chitina Leader (January 28, 1911) reported that natives had observed an increase in the size of the vapor plume issuing from the summit of Mount Wrangell. This increase followed two minor tremors on the morning of January 21, 1911. The following headline account of an eruption from Mount Wrangell appeared in the April 15, 1911, edition of the Chitina Leader: 'Last night about 9:20 p.m. a flash which was at first mistaken for lightning, was observed at the summit of Mount Wrangell. This was followed in a minute or so by another, which was recognized then as a tongue of flame issuing from the crater of the mountain. In about five minutes, an immense volume of fire swept up into the sky * * * Height of the column was judged by the known height of the mountain to have been from two to three thousand feet. This was succeeded by a couple of flashes similar to the first seen after which the giant mountain relapsed into comparative quiet, although clouds of unusually black smoke continued to pour from the main crater for some time afterwards.'
"Reports of eruptive activity continued into mid-November, 1911.
"The Valdez Weekly Miner (April 28, 1912) carried an account from Tonsina ' * * * large clouds of smoke and vapor pouring out of a crater and ascending high into the air.' A prospector from Kotsina reported very strong sulphur fumes on the south-southwest flank and claimed that Mount Wrangell had 'broken out in several different places, all low down on the mountain and a considerable distance from the big crater' (Valdez Daily Prospector, September 13, 1912). The latter may be a reference to the cluster of fumaroles that perforate the glacier ice at about 3660 m (12,000 ft) elevation on the west-southwest flank of the mountain. Another account, appearing in the September 15, 1912, Valdez Weekly Miner claimed that 'lava was flowing down the west flank of the volcano and that great columns of smoke were rising from the mountain top.'"

From Motyka (1983): "Local inhabitants reported a small eruption on July 3, 1921. The plume was seen from Chitina, located southeast of volcano, towering well above Mount Wrangell with the source somewhere on the north flank of the mountain (fig. 7 [a photograph of the event]). This plume was also observed by Wm. Cameron from near Sourdough, which is located northwest of the volcano."

Activity at Mount Blackburn was reported in an Associated Press article published March 26, 1930, but this activity is probably attributable to Mount Wrangell rather than Mount Blackburn. From the article: "Mount Blackburn is erupting again. Chitina residents report that the eruption is spectacular, not to mention huge columns of black smoke."
From Motyka (1983): "Another short eruption is reported to have occurred on April 6, 1930. Again documented by photographs from Chitina, billowy white plumes were observed rising high above the West Crater [see figure 8 in original text for photograph of plume].

From Neal and McGimsey (1997): "A pilot report of a suspicious cloud rising 5,000 feet near Wrangell Volcano prompted satellite analysis and phone calls on January 18, 1996. National Weather Service (NWS) contract observers in Glennallen subsequently confirmed that a robust steam plume had been visible over Wrangell for several weeks. Wrangell has several active fumarolic areas in its summit caldera. These fumaroles frequently produce steam plumes that are mistaken for eruptive activity."

From McGimsey and Wallace (1999): "On June 3, 1997, AVO received a pilot report of steam rising from the summit of Wrangell Volcano. Three weeks later, on June 24, another report described a steam plume rising up to 700 ft (~213 m) above the summit. No sign of activity was observed on satellite imagery and no mention was made in the AVO weekly update. Several active fumaroles in the summit caldera frequently produce steam plumes that are mistaken for eruptive activity."

From McGimsey and others (2004): "On the morning of May 14, 1999, a NWS observer in Gulkana reported anomalous steam - with minor ash - emission at Wrangell Volcano. At approximately 9:30 AM ADT, a sudden, rapidly billowing, grayish and white cloud rose to about 3,000 feet above the north summit crater. The weather was clear with calm winds out of the south. The observer stated that at this time of year, on clear days, a small, wispy, steam plume is usually visible above Wrangell in the early morning, and dissipates by early afternoon. On this day, the plume developed quickly, was abnormally voluminous, and had a grayish color.
"We learned from interviewing a local pilot (Lin Ellis), flying a routine mail run, that he had also observed the activity at Wrangell while passing by the south-southwest flank at 10,000 feet ASL. Additionally, he noticed that more 'dirt' surrounded the north crater than usual, and, that on the upper part of the Chestnina Glacier - high on the southwest flank - blocks of ice were chaotically
jumbled (higher relief between blocks) and that the glacier surface was much more crevassed than he had ever previously seen. He also observed that of two known fumaroles located at about the 11,000-foot level (3,350 m) on the south flank that typically issue steam through ice holes, one was now surrounded by a sizeable patch of bare rock. This, too, was a new development since his
last recent flight over the area. Ellis further reported that he had seen no sign of flowage or melting events (high on flank), but that he had not flown over the lower reaches of the glacier.
"As of 5 PM, the NWS observer in Gulkana could still see a small steam plume and with binoculars could see that the snow around the summit area appeared to be light gray and that this was a definite color contrast and not an effect from shadows. AVO conducted follow-up phone calls to confirm that activity had returned to 'normal'.

From Neal and others (2004): "AVO received word from a Trans Alaska Pipeline worker of an unusually strong, white steam
plume from Wrangell between 0500 and 0600 AST on March 18, 2000. Later that day, a National Park Service employee in Kenny Lake reported robust steaming over the past month from multiple sources on the southwest flank of the volcano, between approximately 2,000-5,000 feet (600-1,500 m) below the summit. AVO found no anomalies in satellite imagery related in time to either report and concluded that no significant unrest had occurred."

From Neal and others (2005): "On August 1, 2002, a spectacular, clear day in south-central Alaska, AVO received several calls reporting an eruption of Mount Wrangell. Callers reported a dark cloud drifting downwind from the general summit area and a dark deposit high on the snow-covered flank of the volcano.
"AVO seismologists checked data from the Wrangell seismic network and, based on a lack of correlative seismicity, concluded that no eruption or explosion had occurred. AVO also consulted with Wrangell St. Elias National Park Geologist Danny Rosenkrantz, who suggested that high winds had lofted fine-grained material exposed in the area near the summit fumaroles. On August 4, an AVO geologist traveling in the area verifed that a diffuse, light gray stripe extended a short distance down the flank of the volcano, emanating from the western rim of the caldera.
"Subsequently, AVO received a video from Copper Center resident Brad Henspeter who witnessed the event on August 1. The tape is just a few minutes long and shows the waning portion of the event at approximately 1:15 pm ADT. In a written accompaniment to the videotape, Henspeter added his own commentary and recollections of the most significant portion of activity. Notable excerpts from his words follow: ‘..ash was dark black . . and billowing . . . multiple billows (puffing) coming one after the next, nearly touching each other. The wind where we were standing was still, however at the top of the mountain the wind was directly from the east . . .the billows were not rising above the top of the mountain.' By the time he and his son returned to a good vantage point to film, about 10-12 minutes later, the billowing had stopped and the 'puffs' had 'turned a more grayish color.'
"In the video, there are indeed discrete, light gray 'puffs' that moved downwind and retained their individual.integrity. There are no other weather clouds in the vicinity. A.light gray, relatively motionless and irregular-shaped cloud sits in the vicinity of the caldera rim. There is a good breeze at ground level (indicated by motion in the trees) but at altitude, clouds are not shearing rapidly. High on the snow-covered flank, a gray-colored swath extends from a high point that we identify as the west caldera rim near Mount Wrangell Crater. The end of the video footage shows two distinct dark areas on the rim that is normally snow-covered. Henspeter's son reported a similar but more vigorous event on August 2, 2002 at about the same time of the day, but AVO received no further inquiries or reports.
"AVO concluded that no volcanic process of significance was involved and no formal information releases were issued. However, these observations remain enigmatic: lack of any seismicity would seem to preclude a phreatic or magmatic eruption and yet the pulsatory, 'puffing' nature of the dirty clouds is difficult to reconcile with a wind phenomenon."

From McGimsey and others (2005): "Danny Rosenkrans, geologist for the Wrangell-St. Elias National Park and Preserve, contacted AVO on June 13, 2003 with photographs taken by a local resident on June 11, 2003 showing an unusual, towering, cloud over the summit area of Mt. Wrangell (fig. 4). Although the cloud might simply have been a common cumulus cloud fortuitously located at or near the summit, the lack of other cumulus clouds in the area over nearby Mts. Drum and Sanford suggest that instead, calm weather conditions permitted steam emissions from the known summit fumaroles to coalesce and form the plume-like cloud over Wrangell. AVO receives several reports per year from pilots and local residents who observe what they consider to be larger than normal steam clouds situated over the summit."
"On September 18, 2003 the Center Weather Service Unit (CWSU) called at 12:50 pm ADT with a Pilot Weather Report (PIREP) of a '2,000-to 2,300-foot-high steam plume' over Mt. Wrangell. The pilot reported no ash or sulfur smell. AVO scientists checked satellite imagery and seismograms and found nothing unusual."

From Neal and others (2014): "No eruptive activity or significant unrest occurred at Wrangell in 2010. However, AVO received an interesting new image of the summit region as well as a report of possible vapor emission from the summit area.
"In May 2010, a single lidar swath over the summit of Wrangell was flown by UAFGI glaciologists Paul Claus and Chris Larsen. The resulting processed image depicts the topography of North Crater, a long-known fumarolic source on the northwestern rim of the ice-filled summit caldera. The characteristic higher northern and lower southeastern rim of the crater is clear in a cross-section of the lidar-derived topography. Within North Crater, there are several secondary depressions including a complex, kidney-bean shaped pit about 20 m (65 ft) deep and 200 m (660 ft) across, located in the center of the crater. This result is broadly consistent with previously recorded surveys of North Crater using photogrammetric techniques (Benson and others, 2007).
"In early November, a long-time resident from the Copper River valley called AVO to report 'more activity at the Mount Wrangell summit than he had ever seen before.' He sent AVO several images of the volcano taken on November 2. The observer reported that when the activity in question began, there had been no weather clouds in the area. He noted about ten 'bursts' from the summit and said this was unusual compared to the typical steady emissions often seen above the volcano. AVO reviewed available seismic and satellite data and, finding no evidence of volcanic signals, concluded that the phenomenon was most likely weather related."

From Herrick and others (2014): "On March 11 [2012], observers in Glennallen noted 'puffs of steam' and called the State of Alaska Department of Homeland Security and Emergency Management office with their concerns. AVO was also contacted and analysts were able to see small plumes above known fumaroles in satellite images.
"On March 20, a citizen noticed unusually rigorous steaming at Wrangell while driving towards to volcano from Valdez. Steam rose from the summit as well as a location on the southwestern flank at about 3,000 m (10,000 ft) ASL and the citizen described the volcano as looking like 'a pressure cooker shot through with nails'. There also were calls to the observatory on June 21 due to concerns about substantial plumes visible from various vantage points in the Copper River basin. No other evidence of significant volcanic unrest was detected, thus AVO concluded these events were likely generated by normal fumarolic activity. No further response activities were required."