Not that many of the world’s favorite and most famous artists have last names beginning with the letter ‘O’. Even Wikipedia’s list of ‘O’ painters is shorter than it is for many of the other letters and includes many painters who simply do not belong in that category.
The good news is that there are plenty of wonderful famous O artists. So far, we have only three painters here but they specialized in very different subject matter. Danish artist Henrik Olrik was known for his portraits. The Spanish artist Martin Rico Ortega is most well-known for his paintings of the city of Venice and American painter Edmund Henry Osthaus is most remembered for his paintings of sporting dogs.