Q:Given the following passage  "After annexing the County of Portugal into one of the several counties that made up the Kingdom of Asturias, King Alfonso III of Asturias knighted Vimara Peres, in 868 AD, as the First Count of Portus Cale (Portugal). The region became known as Portucale, Portugale, and simultaneously Portugália — the County of Portugal. Later the Kingdom of Asturias was divided into a number of Christian Kingdoms in Northern Spain due to dynastic divisions of inheritance among the kings offspring. With the forced abdication of Alfonso III "the Great" of Asturias by his sons in 910, the Kingdom of Asturias split into three separate kingdoms of León, Galicia and Asturias. The three kingdoms were eventually reunited in 924 (León and Galicia in 914, Asturias later) under the crown of León.",  answer the following question. Note that the answer is present within the text.  Question: when did the kingdom of asturias split into three separate kingdoms?
A:
910