Relations between Grand Lodges are determined by the concept of Recognition. Each Grand Lodge maintains a list of other Grand Lodges that it recognises. When two Grand Lodges recognise and are in Masonic communication with each other, they are said to be in amity, and the brethren of each may visit each other's Lodges and interact Masonically. When two Grand Lodges are not in amity, inter-visitation is not allowed. There are many reasons why one Grand Lodge will withhold or withdraw recognition from another, but the two most common are Exclusive Jurisdiction and Regularity. 

Since the middle of the 19th century, Masonic historians have sought the origins of the movement in a series of similar documents known as the Old Charges, dating from the Regius Poem in about 1425 to the beginning of the 18th century. Alluding to the membership of a lodge of operative masons, they relate a mythologised history of the craft, the duties of its grades, and the manner in which oaths of fidelity are to be taken on joining. The fifteenth century also sees the first evidence of ceremonial regalia.
When was the Reglus Poem noted?
 dating from the Regius Poem in about 1425