Sancho I of Aragon

Sancho Ramírez
Sancho (Sancius filius, Sancho the son) with his father, King Ramiro (Ranimirus rex) From a thirteenth-century manuscript of Jaca
King of Aragon
Tenure	1063 - 1094
Predecessor	Ramiro I
Successor	Peter I
King of Pamplona
Tenure	1076 - 1094
Predecessor	Sancho IV
Successor	Peter I
Born	c. 1042
Died	1094
Spouse	Isabella of Urgell Felicia of Roucy
Issue	Peter Fernando Alfonso Ramiro
House	House of Jiménez
Father	Ramiro I
Mother	Ermesinda of Bigorre
Religion	Catholicism

Sancho Ramírez (c. 1042 - 4 June, 1094) was King of Aragon from 1063 until 1094 and King of Pamplona from 1076 under the name of Sancho V (Basque: Antso V.a Ramirez). He was the eldest son of Ramiro I and Ermesinda of Bigorre. His father was the first king of Aragon and an illegitimate son of Sancho III of Pamplona. He inherited the Aragonese crown from his father in 1063. Sancho Ramírez was chosen king of Pamplona by Navarrese noblemen after Sancho IV was murdered by his siblings.

Sancho Ramírez succeeded his father as second King of Aragon in 1063. Between 1067 and 1068, the War of the Three Sanchos involved him in a conflict with his first cousins, both also named Sancho: Sancho IV the king of Navarre and Sancho II the king of Castile, respectively. The Castilian Sancho was trying to retake Bureba and Alta Rioja, which his father had given away to the king of Navarre and failed to retake. The Navarrese Sancho begged the aid of the Aragonese Sancho to defend his kingdom. Sancho of Castile defeated the two cousins and retook both Bureba and Alta Rioja, as well as Álava.

Sancho Ramírez followed his father's practice, not using the royal title early in his reign even though his state had become fully independent. This changed in 1076, when Sancho IV of Navarre was murdered by his own siblings, thus prompting a succession crisis in this neighboring kingdom that represented Aragon's nominal overlord. At first, the murdered king's young son, García, who had fled to Castile, was recognized as titular king by Alfonso VI, while Sancho Ramírez recruited to his side noblemen of Navarre who resented their kingdom falling under Alfonso's influence. The crisis was resolved by partition. Sancho Ramírez was elected King of Navarre, while he ceded previously contested western provinces of the kingdom to Alfonso. From this time, Sancho referred to himself as king not only of Navarre but also Aragon.