A hundred years ago today (October 12, 2025), the People's Revolutionary Party of Inner Mongolia ᠳᠤᠲᠤᠭᠠᠳᠤ ᠮᠤᠩᠭᠤᠯ ᠤᠨ ᠠᠷᠠᠳ ᠤᠨ ᠬᠤᠪᠢᠰᠬᠠᠯᠲᠤ ᠨᠠᠮ 内蒙古國民革命黨 held its first (and only) conference in Zhangjiakou (ᠴᠢᠭᠤᠯᠠᠯᠲᠤ ᠬᠠᠭᠠᠯᠭ᠍ ᠠ ᠌"Kalgan"). It was an important event in Mongolian history -- all the subsequent left-nationalist governments of Inner Mongolia (including that of the Inner Mongolian Autonomous Gov't and its successor autonomous region) traced their political origins to this congress. Here are some visuals of this party and its successors over time.

Presidium of the 1st Central Committee of the PRPIM:
Seated (from left): AltanOchir, Fumingtai (Buyangerel) Merse, Bai Yunti (Serengdonrub), Murungga (Yue Jingtao), Sainbayar, Mandaltu
Standing (from left): Byannemekh (alias Cecenbiligtu), Dambadorj, A.I. Oshirov (Comintern representative)

Party Membership Card, cover
The blue flag with a white star, and the word Monggol in a circle in the center, was the party flag

Provisional Assembly of the PRPIM, July 26, 1925
Seated, from left: Bai Yunti (Serengdonrub), Gobol Erkhimbatu, Fumingtai (Buyangerel), Engkhebatu, Gurusede (?), Wangdanima, Gurusede's wife, Wangdanima's wife, Bai Yunti's wife
Standing (from far left): Nimajab, Erintsen, Mandaltu, Sainbayar, Murungga (Yue Jingtao), Dechin, AltanOchir, Alta, three unidentified candidate members)

Inner Mongolia People's Journal (organ of the party, first issue, November 16, 2025)
The figure on the right is carrying the party flag

Cover of the Party's Program, October 1925
The flag is the flag of the provisional government which the party founded in Juu Uda -- like the flag of the Nationalist Government of the time, the field was red, with a blue canton, and a white symbol in the canton -- but instead of the KMT sun, the symbol was the white star.

Delegates to the October Congress of the PRPIM

Flag of the Inner Mongolian People's Revolutionary Youth League, September-November, 1945
The founders of this youth league were inspired by PRPIM members

Redrawn Version of the Flag of the Inner Mongolian People's Revolutionary Youth League

Flag of the East Mongolian Autonomous Government, September 1945 - April, 1946
This government was founded by PRPIM members, who saw themselves as the PRPIM Eastern Branch