It is located on the Skaggerak coast in Southern Norway along the Groosefjorden, between the towns of Arendal (to the northeast) and Lillesand (to the southwest).

Grimstad Church is located on a small hill overlooking the town's harbour.

The village of Grømstad existed for a long time as part of the ancient prestegjeld of Fjære.

On 1 July 1532, he surrendered to his rival, King Frederick I of Denmark, in exchange for a promise of safe conduct.

John Frederik Classen, who owned the Frolands Værk (an ironworks located nearby), obtained concessions to export and import through Grimstad and bypass Arendal with its customs dues.