The Constitution of independent India came into effect on Republic Day, January 26, 1950. This date was chosen as it was the anniversary of an earlier celebration Purna Swaraj "complete self-rule" Day, which was on January 26, 1930.
Every January 26, large military parades are held in New Delhi and the state capitals with representatives of the Indian Army, Navy and Air Force and traditional dance troupes taking part.
The grand parade in New Delhi starts with India's Prime Minister laying a wreath at the Amar Jawan Jyoti "the flame of the immortal soldier" at India Gate. Jawan (like the Australian Army "Digger") is a term of considerable pride.
January 26 is also Australia Day.
Happy India Republic and Australia Day.