BY THE ARCHAEOLOGIST EDITOR GROUP
Based on two distinct readings of the question, there are two plausible responses to this; however, one of them calls for a minor grammatical adjustment to the original query.
who were the historic Knights Templar?
When the First Crusade took Jerusalem, some of its soldiers had the wild idea: "Let's establish a monastic order (there were several at the time, and new ones were regularly founded), but instead of being pacifists, we will be aggressive monks who fight heretics, heathens, and unbelievers. To keep genuine Christians safe in the world, we shall battle against them.
They lived in monasteries, as did all monastic orders, and new members gave all of their possessions to the Order in exchange for the right to use the tools that were provided to them. They took an oath, promising to be poor, chaste, and obedient. The Temple of King Solomon was destroyed by the Romans while the founders were standing on the Temple Mount, a ruin. The Knights Templar was the name given to the order because its founders chose to locate its headquarters on the Temple Mount.
They were some of the most well-trained and disciplined soldiers in the entire Christian world throughout the 200 years they existed. They also created international banking along the way, but that is a topic for a different inquiry.
The original Knights Templar are therefore nonexistent. A contemporary organization, though, goes by the same name.
when politics happened and they got disbanded
The idea that they didn't break up but rather went into hiding is a fun and exciting concept in fiction. Simply put, this is untrue. Since the original Knights Templar are no longer in existence, joining them is not an option.
But the best way to find out historically how someone might have joined the Knights Templar is to visit one of their monasteries and inquire. You would be a prospective member for a while, and if you didn't like it or they didn't like you, you could leave without any consequences. If you do get along after some time, you may swear the oath and join as a full member. It was that easy, but there was a lot of work involved, so it wasn't straightforward.
The Modern Knights Templar
The original Knights Templar are therefore nonexistent. A contemporary organization, though, goes by the same name. They have no connection to the legendary Knights Templar and are an entirely different group. Yet they elected to use that name since the legendary Knights Templar served as an inspiration to them.
This group is a Masonic Associated Body. As a result, although they are distinct from the Free Masons, they exclusively hire from among them. Hence, being a Master Mason is a prerequisite for joining the Knights Templar. The York Rite of Masonry must thereafter be joined.
Following the three degrees of Regular Masonry, there are 10 degrees of the York Rite (commonly known as Red Lodge) (also called Blue Lodge). Those ten degrees are not all employed by the same company, though.
The Royal Arch Masonry system includes the first four York degrees (also called chapters). The following three degrees are a part of secretive masons (also called Council). The Knights Templar offer the final three degrees (also called Commandry).
So, you must first become a Mason and finish the three degrees of the Blue Lodge in order to join the Knights Templar. After that, you must enlist in the York Rite and complete all four Chapter degrees. After that, you must complete the three Cryptic Degrees and enter the York Rite's Council section. After that, you must enlist in the last branch of York Rite Masonry. You can only use the title "Knight of the Temple" after that.
For instance, many of the other members of the Blue Lodge are York Rite Masons. At the conclusion of our Blue Lodge sessions, someone will frequently stand up and announce the future York Rite meeting times and dates.
The problem is that Christianity is exclusive to Christians. Men of any faith are welcome to join in on the remainder of Masonry. The only requirement is that you practice some form of religion. The exception is commandry, which is more detailed.
We infer that if you wish to join the Knights of the Temple, you must first be prepared to publicly swear loyalty to Jesus Christ before joining the Masons.
