William Ludwig was born in Wuppertal, Germany, and completed his acting and singing studies in Germany and London. His debut on the musical stage was in the revue It's Showtime in Wuppertal. He went on to appear in Elegies at London's Bridewell Theatre and two lost musicals at the Theatre Museum, A Girl Called Jo and Grab Me A Gondola. William played the lead in a European tour of the pop musical Hot Stuff before returning to London to play an alien in the new musical Into Thin Air at the Charing Cross Theatre. He also appeared as Jack the Ripper (Jermyn Street Theatre) and Buffalo Bill in Annie Get Your Gun at the Union Theatre. He then created the part of Damon Runyon in Kampf des Jahrhunderts at the Tribüne Theatre in Berlin and performed with Sara Kestelman in Coco at the Lilian Baylis Theatre/Sadler's Wells.
In theatre his credits include Loevborg in Hedda Gabler (Greenwich), DeLevis in Loyalties (Finborough Theatre), Hound of the Baskervilles and Great Expectations (Brockley Jack) and a site-specific production of dreamthinkspeak's In The Beginning Was The End at Somerset House. In 2018 he played Colonel Pickering in a major new production of My Fair Lady at the Luisenburg Festival in Germany and in 2020 he performed in a new production of Fidelio at the Royal Opera House with Lise Davidsen and Jonas Kaufmann and conducted by Pappano.
William's concert and cabaret projects have taken him to prestigious venues throughout Europe, including the Gewandhaus in Leipzig and the Munich Philharmonie. Together with West End MD Dean Austin he toured Germany with a highly-acclaimed evening of the songs of Kurt Weill, Youkali. London's Vortex hosted an evening of Berlin Cabaret Songs and Ports Of Call, a programme of German and French cabaret songs, took him to the Grec Festival in Barcelona, a sold-out run at the Edinburgh Festival and London's Drill Hall. William also appeared together with Broadway singer Anne Kerry Ford at New York's Cafe Sabarsky, with Karen Kohler at The Cutting Room and Don't Tell Mama NYC and with Brett Kahr for an evening of Brett's cabaret songs in London. In 2012 William, together with MD Vanessa Williams, reached the finals of the Oltner Kabarett-Tage, Switzerland's largest cabaret festival and competition. William and Dean have performed at London's Crazy Coqs, The Pheasantry and The American Bar at the London Coliseum and with the premiere of The Last Drink at the Ruhrfestival in Germany. He has recorded German cabaret songs with the Pasadena Roof Orchestra. In 2019 William and Dean performed Weimar Cabaret Songs at a charity concert for Bono and Chris Martin and also a series of concerts at the Barbican Art Gallery in London as part of the exhibition Into The Night - The Art of Cabaret.
In film, his credits include Culture Shock (Steve Balderson), Queen And Country (Andrew Faure), Brothers of War (Mike Carter) and The Honourable Rebel (Mike Fraser). 2017 saw the release of Another Mother's Son, starring John Hannah. He has appeared on television in The Spy Next Door (Sky), The Christmas Truce (BBC) and Escape From Sobibor (PBS). William played a lead in the BAFTA-winning short film Dancing In The Ashes, Kaiser Wilhelm in a controversial music video for BBC WW1 Uncut and Louis XIV in a prequel for TV series The Strain for Fox.