Bernard I (or Bernardo, Bernhard) may refer to:
Bernard of Septimania, also known as Bernard I of Toulouse (born 795) Bernard I of Poitiers (died 844) Bernard I of Armagnac (died 995), called 'the Suspicious', first duke of Armagnac Bernard I William of Gascony (died c. 1009) Bernard I, Duke of Saxony (died 1011) Bernard I of Bigorre, (962–1034) Bernard I of Berga, count of Berga in 1035–1050 Bernard II Tumapaler of Gascony (died 1064x1090), sometimes counted as Bernard I Bernhard I, Lord of Lippe (c. 1090 – c. 1158) Bernard I de Balliol (died 1164) Bernhard I, Prince of Anhalt-Bernburg (c. 1218–1287) Bernard I, Margrave of Baden-Baden (died 1431) Bernard I, Duke of Brunswick-Lüneburg (died 1434) Bernardo I of Kongo (died 1567) Bernhard I, Duke of Saxe-Meiningen (1649–1706)