It is believe that this practice can be traced back to several individuals in the past which include Lord Byron, Julius Caesar, Alexander the Great, Leonardo da Vinci, Donatello and many more. Many continue to disagree with Michel Foucault who begs to differ with them when it comes to this particular issue terming it as one that was of a foreign nature during those times.
The nature of same sex relationships in the past was in the form of egalitarian relationships which was the case in Greece formerly. Gay marriages have been considered to have their roots in the West before they started being practiced in other regions around the world. In some situations, there are scenarios where individuals have shared the same identity when in bisexual unions such as in Latin America.
This was not the practice among all the cultures in the past but some such as the Vikings and Saxons are believed to have been practicing such relationships secretly. Another believe among the forces such as the Sacred Band of Thebes was that individuals in same sex relationships had higher motivation when it came to fighting because it was viewed as a source of morale and a catalyst to fighting harder.
This contributed greatly to the unions between those who had been in the military for a long time and those who had just joined in and were learning from the experienced. Japan and Greece are examples of those that engaged in these kinds of relationships. With the passing on of time and changes experienced in the society there was erosion of same sex relationships.