Alfred L. Kroeber suggested that the 1770 population for the Esselen of 500. Esselen 531 until the councils were merged. There are virtually no contemporary records of the Esselen people's lives. Alfred L. Kroeber suggests a 1770 population for the Esselen of 500. Very little information on the vocabulary and grammar of Esselen was preserved. The area was originally populated by Ohlone, Salinan and Esselen tribes. The name "Esselen" was derived from a village name. The Spanish mission system led to severe decimation of the initially small Esselen population. The mission was about from the nearest Esselen territory, Excelen. The Esselen language is a language isolate. Archeological evidence of settlements have been found throughout Esselen territory. Achasta was a Rumsen Ohlone village, and totally unrelated to the Esselen. Robert Sobukwe Street in Pretoria (formerly known as Esselen Street) is named after him. H. W. Henshaw thought that the Esselen people's language represented a monotypic linguistic family. The Esselen was approximately 1.3, the Salinan must have been still lower.