Ireland doesn't celebrate it.
Irish Independence:
The Easter Rising of 1916 is commemorated, but due to the blood sacrifice, while the Proclamation of the Republic is read, it's a ceremony for the dead.
Nothing is celebrated on the 6th of December, likewise nothing is celebrated on the 18th of April for the Declaration of the Republic.
One of the reasons being, Ireland's division was increasing with each milestone of independence. How can you celebrate that?
I have removed several comments in this thread for the same reason: one sentence answers are simply not acceptable as top-tier responses on r/Askhistorians. To make my point clear, an answer along the lines of "yes, my country celebrates it." does not fulfill our expected level of discourse. You can find our expected standards in the sub rules:
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India celebrates independence from Britain on 15th August. Pakistn does the same on 14th August. The two countries gained their independence on the same day, but celebrate it on different days. The only explanation of this that I know of is that Both India an Pakistan wanted Lord Mountbatten to be present at their ceremonies. The ceremony for India was in New Delhi, the one for Pakistan was in Karachi. To resolve the issue, Mountbatten was in karachi on 14th and New Delhi on 15th.
This however is not the end of the story. On 15 August 1947 India did not become a free country. It became a dominion of UK. It would gain complete independence on 26 January 1950 when the Indian constitution came to power. The day 26 january was chosen specifically for its significance to the independence movement. on 26 january 1930 the Declaration of Indian Independence (Purna Swaraj) was proclaimed by the Indian National Congress. 26 january is now celebrated as Republic Day in India, and usually has more elaborate ceremonies.
This is the end of story for celebrating independence from the British, but there were other colonial holdings in India. Goa and other Portuguese colonies would not gain independence till 19 december 1961. This date is celebrated in those parts as 'Liberation Day'