Around here Cinco de Mayo is mostly celebrated in recognition of the battle of Puebla in which the Mexican republicans defeated the French Imperial Army. However, there are far better things I would like to remember the day for. For example, it was on 5 May that the great Kublai Khan became ruler of the Mongol Empire in 1260. On 5 May in 1640 King Charles I of Britain dissolved the Short Parliament (no monarch ever does so great a national service as when they dissolve parliaments). On May 5, 1821 the former Emperor Napoleon I of France died in exile on St Helena island, in 1941 it was the day that Emperor Haile Selassie of Ethiopia returned to his capital and declared May 5 "Liberation Day" and it was on May 5, 1950 that HM King Bhumibol Adulyadej was crowned King of Thailand. He remains the longest serving head of state in the world today.
May 5 is also the birthday of Emperor Uda of Japan, King Alphonso III of Portugal, Holy Roman Emperor Leopold II, the French Empress Eugenie and was the wedding anniversary of the late Princess Margaret of Great Britain. Any one of these would be a greater cause for celebration than the battle of Puebla and the victory of the liberal, anti-clerical, republican government of Benito Juarez. May 5 is also the feast day of Pope St Pius V who famously reformed the Catholic Church and dispatched the Christian fleet that won the epic battle of Lepanto in the Mediterranean. Certainly a far more worthy figure of celebration than a republican victory in Mexico.