Some authors think that the name of the town derives from the German toponym Hlaeri, meaning wasteland or common grazing land, while others suggest an origin in the German Fliessen, from the Dutch vliet or the Latin fluere Latin Fluere, indicating a waterflow, basin or marsh.

Finally, the Breton term fler or flear means bad smell, indicating the stench of stagnant water.

Tradition has it that in the 11th century, the two brothers Foulques d'Aunou and Guillaume de Gasprée married two sisters who were Ladies of Flers.

[5] The construction of the castle of Flers began in the 12th century as a fortified location of wood and stone surrounded by water.

The chronicles of the Hundred Years War do not mention a fortified place in Flers, revealing that it didn't present a major strategic interest at the time.

Like other towns near the D-Day landing, Flers was one of the targets of strategic bombing of Normandy on 6 and 7 June 1944, aimed at reducing the advance of German reinforcements.

It has a local bus system for Flers and the surrounding communities, and departmental lines connecting it with other major towns in Orne and Calvados.