Second Battle of Kharkov

The Second Battle of Kharkov, so named by Wilhelm Keitel, was an Axis counter-offensive in the region around Kharkov (now Kharkiv^[10]) against the Red Army Izium bridgehead offensive conducted 12–28 May 1942, on the Eastern Front during World War II. Its objective was to eliminate the Izium bridgehead over Seversky Donets, or the "Barvenkovo bulge" (Russian: Барвенковский выступ) which was one of the Soviet offensive's staging areas. After a successful winter counter-offensive that drove German troops away from Moscow, and also depleted the Red Army's reserves, the Kharkov offensive was a new Soviet attempt to expand upon their strategic initiative, although it failed to secure a significant element of surprise.

• http://en.wikipedia.org/wiki/Second Battle of Kharkov