English: Old runic calendar from Saaremaa in Estland.

Quote from the Wikipedia article: "The name Eysysla appears sometimes together with Adalsysla, "the big land", perhaps 'Suuremaa' or 'Suur Maa' in Estonian, which refers to mainland Estonia. In Latvian, the island is called Sāmsala, which means "the island of Saami""[1]

Øsel is the name of the island when it was under Danish rule in the medieval period, and the Swedish with the name Ösel. The ancient Greek - Phonicians and culture of the pre-christian Roman Empire likely influenced these Baltic and Nordic runic scripts.

People with the runes likely came to the Nordic and Estonian - Baltic areas with the Iron-Age Indo-European people connected to the Early Roman Empire. This period is archaeologically named: The Roman Nordic Iron Age. A people that from early on merged with the indigenous people and that later were displaced from the areas they inhabiated in the Nordic by the Dacian people that came from Eastern Europe to the northwestern and the Nordic areas during the medieval period.