I did not know that yesterday!

That sweet red blotch inside a tart green olive has always been a puzzler.
To answer part one of the question, I headed straight for Epicurious.com, where I found the following definition:


pimiento; pimento A large, red, heart-shaped sweet pepper that measures 3 to 4 inches long and 2 to 3 inches wide. The flesh of the pimiento (the Spanish word for "pepper") is sweet, succulent and more aromatic than that of the red bell pepper... Pimientos are the familiar red stuffing found in green olives. Armed with a new appreciation for sweet peppers, I entered "olive + pimento" and "olive history" in the Google search box, hoping to answer the second part of the question. I couldn't find a specific reason as to where or why the practice of stuffing olives with pimentos started, but I did find some interesting facts about olives that may hint at a reason.

First, Spain leads the world in olive production, followed by Italy and Portugal. Since "pimento" is a Spanish word, I'm guessing maybe they started the pimento practice. That answers the where, now for the why.

All freshly picked olives, no matter how ripe, have a vile, intensely bitter taste. In order to make them palatable, they must be pickled. Since pimentos are sweet and indigenous to the Mediterranean, it's easy to imagine an innovative farmer or chef way back when thinking they would make the perfect neutralizer to the olive's natural
acidity. After all, aren't the best dishes created with ingredients most readily available?

While this is all speculation, if you visited a Spanish tapas bar and sampled a variety of olive offerings, you'd see my point. So pour yourself a martini and puzzle no more.