Battle of São Mamede

The Battle of São Mamede (Batalha de São Mamede in Portuguese; pron. IPA []) took place on June 24, 1128 and is considered the seminal event for the foundation of Portugal. The battle occurred near Guimarães. Portuguese forces led by Afonso I of Portugal defeated forces led by his mother Teresa of Leon and her lover Fernando Perez de Trava. Following St. Mamede, the future king styled himself "Prince of Portugal". He would be called "King of Portugal" in 1139 and was recognized as such by neighbouring kingdoms in 1143.
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