By Staffan Fridell
The Viking Age rune stone U 170 at Bogesund in Vaxholm had been lost since the 17th century when part of it was rediscovered in 2013. The inscription refers to a man who died i akru. This name has been interpreted either as a compound form *Ækrøy < *Æikʀøy ‘the oak island’, or as a derivative *Ækra < *Æikra < *Aikrōn of the word for ‘oak’, and has been identified in both cases with Ekerö on Lake Mälaren. The author subscribes to the interpretation *Æikra, but argues that akru could just as easily refer to Eckerö (in the Åland Islands), which probably has the same etymology. A likely parallel formation to *Æikra is the lake name Eckern in northern Småland, whose Old Swedish form is Æker < *Æikr < *Aikraʀ.