<page_title> List of most successful U-boat commanders </page_title> <section_title> World War I </section_title> <table> <cell> 6 <col_header> # </col_header> </cell> <cell> Walther Schwieger <col_header> Commander </col_header> </cell> </table>
Walther Schwieger was the sixth most successful submarine commander of World War I.