This is Deciderius Erasmus. I bet that before now, you didn't know how to speak his name! He's rather attached to his book, isn't he? In every single picture up there, his book is right there at his side.
He was a Catholic priest who acted as some sort of unwilling reformer. Born in 1466, his work was definitely cut out for him when poverty forced him into being a Catholic priest at the age of 26. From this new position, he wanted to "return Christian goodness" and reform the church from within. He was such an amazing man, in fact, he was two-faced; while he did support Protestant ideals (but not their leaders), he argued that he wasn't actually a Protestant.
In reality, he was one of the most outspoken contributers to the call for reform. The book he wrote, The Call For Folly, belittled his peers the clergy and the church leaders. This actually backfired on him, as his harsh verbal bombardment warded people away from joining his perspective. He died in 1536.