Eystein I, also known as Eystein the One-Eyed, was a king of Norway who ruled during the early 12th century. He was a member of the House of Knýtlinga and is often remembered for his efforts to consolidate power in the region. His reign is noted for the establishment of stronger ties with neighboring kingdoms. Eystein I was a contemporary of other notable rulers, including Sigurd I, his half-brother. He is recognized for his military campaigns and attempts to expand Norwegian influence. His legacy includes contributions to the development of a more unified Norwegian state during a time of political fragmentation.