Complex sentence: However, on February 23,1918, political sovereignty was granted to the Polish National Committee and soon other Polish units were formed, most notably the 4th and 5th Rifle Divisions in Russia.
Split into simpler sentences: However, on 23 February 1918 political sovereignty was granted to the Polish National Committee, and soon more Polish army units were formed. Most notably the 4th and 5th Rifle Divisions in Russia.