In the Year of Our Lord 1035 Sancho III Garcés, King of Navarre by birthright and King of León by conquest, took his last breath and plunged Christian Spain into chaos. For he had devised that his lands should be divided amongst his sons. The eldest, García, became King of Navarre, Gonzalo had the counties of Sobrarbe and Ribagorza, and Ferdinand was Count of Castile. Lastly, his eldest but illegitimate son, Ramiro, was given the county of Aragón to rule. As was the wont of sons of royal blood in that time and age, they soon raised their banners against each other in bloody conflict. It started in the decade after their father's death, when Gonzalo was assassinated and Ramiro convinced García, who was his nominal overlord, to grant him Sobrarbe and Ribagorza. Not long after, Ramiro, backed by the Muslim ruler of Zaragoza, invaded Navarre when he thought García weak. His half-brother called upon Ferdinand to support him, and Ramiro was defeated. Of the three brothers, Ferdinand was most successful, first defeating Bermudo III of Léon, who had taken back his kingdom after the death of Ferdinand's father, and then in AD 1054 his elder brother García, from whom he took back the region of Bureba. Ramiro's attempts at military expansion were less fruitful, and his desire for expansion became his end when trying to take the town of Graus in AD 1063.
It was up to his son Sancho Ramírez to lead the fledgling kingdom of Aragón to the greatness that Ramiro had aspired to. It seemed to start well, as in the same year his father died, Pope Alexander II preached in favour of the Spanish Reconquista. From the north, the French and the Burgundians answered the call and from Italy came Norman contingents. The crusaders met in Aragonese lands and joined Sancho's forces in an assault on the city of Barbastro. Though the siege was a success, the armies were disbanded too soon and in AD 1065 the Muslims came with an army and retook the city. More misfortune became Sancho Ramírez the same year, when his two nephews, the kings of Castile and Navarre started fighting over contested lands in the Rioja region. Sancho IV Garcés of Navarre called upon Aragonese assistance, as Sancho Ramírez in his careful diplomatic play still recognised the King of Navarre as his nominal overlord. The so called 'War of the Three Sanchos' ended in defeat, Sancho II of Castile consolidating his powers further. A lull in action was ended when in AD 1076 Sancho IV Garcés became target of fratricide at the hands of his brother and sister. Alfonso VI of León and Castile, who had succeeded his brother Sancho II after the latter had been assassinated in AD 1072, was quick to claim that the Navarrese throne should be his. However, the nobles of Navarre supported Sancho Ramírez instead, mainly because the vassals of Aragón enjoyed far more autonomy than their equals in Castile did. The issue was eventually settled diplomatically, Alfonso gaining permanent control over the previously contested regions of Álava, Bureba and Rioja, and Sancho receiving the kingship of both Aragón and Navarre as recognised by Alfonso.
This is the situation that you enter at the start of the campaign in AD 1080. In the boots of Sancho Ramírez you rule the joint kingdoms of Aragón and Navarre, comprising a relatively insignificant string of counties straddling the lower reaches of the Pyrenees. Small towns dot the valleys carved out by rivers like the Aragón, the source of the kingdom's name. Of these towns, Jaca is the capital of the original lands of Aragón, and during his reign Ramiro bestowed it its city charter and, just before his death, had it made the seat of the diocese of Aragón (or Jaca-Huesca). Pamplona, the capital of Navarre, was a greater city still, though dwarfed yet by the cities of Andalusia to the south. None of these towns are of an inspiring greatness, and many a man would could the lands of the King of Aragón small and poor.
The kingdom is certainly not as strong as it wants to be. Its landlocked position and pastoral economy means that it cannot match the wealth of Mediterranean Iberia. Similarly, its limited and sparsely populated land means that in terms of manpower it is unable to compete with its big neighbour of León-Castile in the west and even struggles to match the strength of the rival taifa of Saraqusta to the south. Yet historically it was capable of carving out one of the most powerful kingdoms of medieval Europe. This potential is there due to the strong diplomatic situation of the young kingdom. The relations with its Christian neighbours, though not always perfect, are good enough to ensure some security. More importantly, the Papal approval of the Reconquista provides the opportunity to wage war with the Islamic neighbours at will.
How to achieve such lofty goals as crowning yourself Emperor of all Spain, the ambition of all Spanish kings, is for you to decide, but remember:
The Dominion of the Sword is only for those who wield it.