This is Edward Carpenter's study of (primarily male) friendship, which in this case is a thinly veiled codeword for 'homosexuality'. In earlier cultures, particularly classical antiquity, but up to and including Elizabethan times, intense, even romantic emotional relationships between men were accepted by society. Paradoxically, these relationships between men were often in the context of cultures which disparaged same sex eroticism, but had no problem accepting these strong bonds between men.
Many of these were true life-long same-sex unions, by the contemporary definition. Outstanding actors on the world stage, men of literature, the arts, and political leaders turn up in this anthology:--the biblical David, Alexander the Great, Michelangelo, Shakespeare, Wagner and 'Mad' King Ludwig, and many others.