A new paper published in Quaternary Science Reviews finds an Arctic Norway glacier was smaller than the present for most of the past 10,000 years of the Holocene. For ~5,500 years during the Holocene Climate Optimum (~10,000 to ~4,000 years ago), the glacier either completely disappeared or was "much reduced" in comparison to the present day extent. The glacier began to regrow ~4,000 years ago in a neoglacial period which peaked during the Little Ice Age ~450 years ago, and which continues at present day.
The paper adds to others finding many glaciers were smaller than the present during the Holocene Climate Optimum and Medieval Warm Period. In addition, other researchers have found worldwide glacier retreat has decelerated since 1950, opposite to the pattern expected if AGW was the primary cause.