From March 31, 2011 (the same day as Shelby Harris, who succeeded Breuning as the oldest living man in the United States, celebrated his 110th birthday), Breuning was hospitalized for an unspecified illness, possibly pneumonia. He died of natural causes at the hospital on April 14, 2011 at 3.30pm aged 114 years, 205 days as the third-youngest of only six men (before Jiroemon Kimura became the oldest man ever in late 2012) who have become at least 114 years old, and was survived by his niece, 3 nephews, and a great niece and nephews. He was succeeded as the oldest living man by Japaneseman Jiroemon Kimura, who was 30 weeks younger and later become the oldest man ever. Breuning and Kimura were, after 110-year-old Japaneseman Tokio Watanabe's death on February 6, 2010, the last two living men born before 1900, as well as the only two men born before 1900 who were still living in the 2nd decade of the 21st century (2011–2020).