Direct proof of use
The documented 2014 Russia-Ukraine War use of the M101 family begins with Lithuanian transfers in September 2022. Lithuania's Ministry of National Defence said on September 8 that 105 mm howitzers were on the way to Ukraine, and LRT reported the same day that Defence Minister Arvydas Anusauskas described them as M50/M101 105 mm howitzers from Lithuanian Armed Forces reserve stocks.
Open-source battlefield reporting then connected those transferred guns to Ukrainian use. Defense Express reported on November 27, 2022 that open footage indicated Ukrainian fighters had begun using Lithuanian M101 105 mm howitzers, while Army Recognition reported the next day that a video showed Ukrainian armed forces using Lithuanian-donated M101A1 105 mm towed howitzers to shell Russian troops.
Sources: Lithuanian MoD Ramstein Howitzers, LRT Reserve Howitzers, Defense Express M101 Use Video, Army Recognition M101A1 Use
Timeline
On September 8, 2022, Lithuania publicly placed 105 mm howitzers in the Ukraine aid pipeline during the Ramstein-format support effort. LRT's report specified the reserve guns as M50/M101-family 105 mm howitzers.
By late November 2022, the first widely cited open-source footage of Ukrainian M101/M101A1 use had appeared. The available reports did not identify a precise front-line location, but they did identify the user as Ukrainian forces and the source of the guns as Lithuania.
Sources: Lithuanian MoD Ramstein Howitzers, LRT Reserve Howitzers, Defense Express M101 Use Video, Army Recognition M101A1 Use
Narrative
In Ukrainian service, the M101 filled a light towed-artillery role rather than a long-range strike role. Reporting described the guns as older 105 mm weapons useful for infantry-support fire, with lower range and explosive weight than the 155 mm systems also supplied to Ukraine.
The Armourers Bench tracked subsequent M101 sightings after the first late-2022 footage, including additional firing clips and later images attributed to Ukrainian units. Those later sightings support continued presence in Ukrainian service, but several of them came from social-media footage with unclear original filming dates or exact locations, so the strongest catalog claim remains transfer by Lithuania and documented Ukrainian artillery use from late 2022 onward.
Sources: Army Recognition M101A1 Use, Armourers Bench M101 Antique