Complex sentence: From 1837 to 1907, the "Telegraph" had a German-language sister publication, known as "Der Wahrheitsfreund"; it was the country's first Catholic periodical published in German.
Split into simpler sentences: From 1837 to 1907, the "Telegraph" had a German-language sister publication, known as "Der Wahrheitsfreund". It was the country's first Catholic periodical published in German.