Complex sentence: The boy's education was undertaken by his uncle Martin Maier, parish priest at Rothenburg on the Neckar, who sent him at the age of twelve to the university of Heidelberg, and subsequently to those of Tübingen, Cologne and Freiburg in the Breisgau.
Split into simpler sentences: The boy's education was undertaken by his uncle, Martin Maier, parish priest at Rothenburg on the river Neckar. At the age of twelve, he was sent to the University of Heidelberg, and subsequently to those of Tübingen, Cologne and Freiburg in the Breisgau.