Gregor Mendel was a 19th century Austrian monk and scientist who is widely considered to be the founder of modern genetics. He conducted experiments with pea plants and developed the laws of inheritance, which laid the foundation for the science of genetics. His work was largely unknown until the early 20th century, when his theories were rediscovered and became the basis for modern genetics. Mendel's work has had a lasting impact on the field of genetics and continues to be studied today.