Sancho Ramírez was King of Aragon from 1063 until 1094 and King of Pamplona (later known as Navarre) 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 (later known as Navarre) by Navarrese noblemen after Sancho IV was murdered by his siblings.
Sancho Ramírez married Isabella of Urgell, daughter of Ermengol III, Count of Urgell around the year 1062. They had one known child, Peter (known as "the Catholic"), who ruled as King of Aragon and Pamplona from 1094 until 1104.
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.