It's often an interesting exercise to learn a little more about the poet whose words you are reading. Some idea of what things shaped their lives, when and where they lived, and the people and events that influenced them -- these things can add layers of meaning to a poem, and provide a better context for understanding and appreciating their works.
The opposite also holds true. Many a well known public figure whose lives you may think you know, produced poems that give a better appreciation of their viewpoint. They become more human and less of an textbook icon.
These summaries are intentionally brief, but packed with information nonetheless. If someone, such as a Lord Byron, a Matthew Arnold, a Helen Hunt Jackson, or a Laurence Hope strikes an interest, delve deeper and see what you can find out about them elsewhere. Thanks to Nelson Miller for initiating this biographical index, which we will add to as time permits. By the way, if you ever wanted to be a biographer but get bored with your subject after 2-3 paragraphs - have I got a job for you...
Along with Lives of the Poets, there is a companion page, Faces of the Poets, to give you a more corporeal view. I always like to read the biography first, then look at the portrait and see whether it surprises me, or not.
And yes, my apologies to Plutarch.