Complex sentence: The Chetnik movement in eastern Bosnia, at best a "confederacy of local warlords", was strengthened by mass defections from the Partisans and for a time ruled large parts of the region after making accommodations with the Ustaše regime in May and June 1942.
Split into simpler sentences: The Chetnik movement in eastern Bosnia, at best a "confederacy of local warlords", was strengthened by mass defections from the Partisans. For a time they ruled large parts of the region, after making accommodations with the Ustaše regime in May and June 1942.