Leo Spitzer was a historian who studied the way language has changed over time. He was born in Vienna, Austria in 1887, and he studied languages like German and French. He noticed how languages change, and realized that the study of language change could be important for understanding history. He wrote a book called "Language and Human Nature", which was published in 1924. In this book, he argued that language is more than just words, it is a way of expressing feelings and emotions, and understanding how language has in history. He also argued that language can shape a society, and this idea formed the basis of his academic field now known as the "cultural linguistics" which focuses on the connection between language, culture, and history. In his later years, he wrote about cultural identity and studied how different societies used their language to communicate with one another. He died in 1973, but his work is still used by historians around the world.