Right after Jerusalem was captured during the First Crusade, the kingdom was reigned by Baldwin II. In 1118, a French Knight of Champagne, Hugues de Payens, and eight of his companions offered themselves and their services to defend the Christian Kingdom against the enemies. The knights took a vow in the presence of the Pope.
After they had taken permission from the king, the knights and their first grandmaster resided in a portion of the palace. The initial aim of the founding of the Knights Templars was to protect the traveling pilgrims coming to the Holy Land.
The group didn’t stop there and started digging around the mountains. Through the years, the group accumulated great wealth. In 1225, the monastic order who started with only nine members, was strong enough to enter Europe after the official Church granted official permission to operate in the continent. Not only that, but the Knights Templar gained the support of influential members, like Bernard of Clairvaux, the writer of the first rule that organized the orders.
The group’s wealth, influence, and fame skyrocketed in Europe. There are many factors that contributed to that. Most importantly, when Pope Innocent II issued a bull in 1139, which granted endorsement to the Knights Templar. After that, the monks only answered to the Pope, which thing that led to an unparalleled increase in power and membership. By then, the order had more than 20000 members with various rankings.
It is, without a doubt, that the Templars were the most powerful group of the Crusades. However, their braveness and their war tactics in their battlefields were not their best qualities.
As the order only helped accountability to the Papacy, it ran several business activities and offered banking services in different locations.
A small group of knights in Jerusalem became strong enough to run preceptories covering land from Syria to England and Portugal.