Battle of São Mamede

Part of the County of Portugal leadership

Celebrations of the Battle of São Mamede in the Castle of Guimarães

Date	24 June, 1128
Location	Guimarães
Result	Afonso Henriques victory. Afonso takes the leadership of the County of Portugal and paths the way for an independent Kingdom of Portugal

Belligerents

Afonso Henriques

Theresa, Countess of Portugal

Commanders and leaders

Afonso Henriques

Theresa, Countess of Portugal
Fernando Pérez de Traba

The Battle of São Mamede (Portuguese: Batalha de São Mamede, pronounced: [ˈsɐ̃w̃ mɐˈmɛð(ɨ)]) took place on 24 June, 1128 near Guimarães and is considered the seminal event for the foundation of the Kingdom of Portugal. Portuguese forces led by Afonso Henriques defeated forces led by his mother Teresa of Portugal and her lover Fernão Peres de Trava. Following São Mamede, the future king styled himself "Prince of Portugal". He would be called "King of Portugal" in 1139 and was recognised as such by neighbouring kingdoms in 1143.

In late 11th century, Henry of Portugal, a knight from Burgundy and descendant of King Robert II, was in search of adventure in Hispania. He fought the Moors along with Alfonso VI of León. In honour of his fights in Hispania, the King gave him the County of Portugal. This gift came with a reinstated title; because of attempts by the previous holder some years earlier to assert independence, it had been suppressed. Henry became count of Portugal and Theresa, one of Alfonso's daughters, his wife.

In 1095, the county was a dependency of the Kingdom of Galicia, itself a dependency of the Kingdom of León. In 1097 Portugal became a direct dependency of León. However, from the early years of his rule, as he became influenced by the desire of the lords of the county for independence, Henry desired the independence of the county.

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