With the resignation of Pope Benedict, take a look at history's longest-reigning popes, or <a href="index.php?page=&url=http%3A%2F%2Fwww.cnn.com%2F2013%2F02%2F12%2Fworld%2Fgallery%2Fshortest-reigning-popes%2Findex.html">check out history's shortest-reigning popes</a>.<br /><br />No. 10 (10th longest-reigning pope): Pope Urban VIII reigned for 20 years, 11 months and 24 days from 1623 to 1644.
Longest-reigning popes —
With the resignation of Pope Benedict, take a look at history's longest-reigning popes, or check out history's shortest-reigning popes.

No. 10 (10th longest-reigning pope): Pope Urban VIII reigned for 20 years, 11 months and 24 days from 1623 to 1644.
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No. 9: Leo I, both a pope and saint, reigned from 440 to 461, for a total of 21 years, 1 month and 13 days.
Longest-reigning popes —
No. 9: Leo I, both a pope and saint, reigned from 440 to 461, for a total of 21 years, 1 month and 13 days.
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No. 8: Pope Sylvester I reigned from 314 to 335 for a total of 21 years, 11 months and 1 day.
Longest-reigning popes —
No. 8: Pope Sylvester I reigned from 314 to 335 for a total of 21 years, 11 months and 1 day.
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No. 7: Pope Alexander III reigned for 21 years, 11 months and 24 days.
Longest-reigning popes —
No. 7: Pope Alexander III reigned for 21 years, 11 months and 24 days.
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No. 6: Pope Pius VII reigned from 1800 to 1823 for a total of 23 years, 5 months and 7 days.
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No. 6: Pope Pius VII reigned from 1800 to 1823 for a total of 23 years, 5 months and 7 days.
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No. 5: Pope Adrian I reigned for 23 years, 10 months and 25 days, from 772 to 795.
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No. 5: Pope Adrian I reigned for 23 years, 10 months and 25 days, from 772 to 795.
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No. 4: Pope Pius VI reigned from 1717 until his imprisonment, and subsequent death, in 1799. His reign lasted 24 years, 6 months and 15 days.
Longest-reigning popes —
No. 4: Pope Pius VI reigned from 1717 until his imprisonment, and subsequent death, in 1799. His reign lasted 24 years, 6 months and 15 days.
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No. 3: Pope Leo XIII reigned from 1878 to 1903, totaling 25 years, 5 months and 1 day.
Longest-reigning popes —
No. 3: Pope Leo XIII reigned from 1878 to 1903, totaling 25 years, 5 months and 1 day.
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No. 2: Pope John Paul II reigned for 26 years, 5 months and 18 days, from 1978 to 2005.
Longest-reigning popes —
No. 2: Pope John Paul II reigned for 26 years, 5 months and 18 days, from 1978 to 2005.
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No. 1: Pope Pius IX reigned the longest of all popes, from 1846 to 1878, for a total of 31 years, 7 months and 23 days.
Longest-reigning popes —
No. 1: Pope Pius IX reigned the longest of all popes, from 1846 to 1878, for a total of 31 years, 7 months and 23 days.
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