Nearly nine months after losing chunks of the Kursk region to a surprise Ukrainian incursion, Russia announced that its troops have fully reclaimed the border territory. Ukraine denied it, saying the fighting was still ongoing. If confirmed, Moscow’s victory in Kursk would deprive Kyiv of key leverage in U.S.-brokered efforts to negotiate an end to the more than 3-year-old war by exchanging its gains for some of Russia-occupied land in Ukraine. Here are key moments of the battle for Kursk and its impact:A Ukrainian blitzUkrainian forces pushed into Kursk on Aug. 6, 2024, in a surprise attack, with battle-hardened mechanized...