It is in the Irish language. It is known as Amhrán na bhFiann, and is sung in Irish. In English it is called The Soldier's Song.
India and Bangladesh. Their national anthems are in Bengali language which is not their national language.
sanskrit
(See related Link) This is a link to a youtube video of someone performing the national anthem in sign language.
Hafeez Jalandhry wrote the national anthem of Pakistan in Persian language.
bengali
Croatian
The National Anthem of India was first written in Sanskritized Bengali originally.
National Anthem of Pakistan is in Persian language. The lyrics of the anthem were written by Hafeez Jallundri in 1950. The anthem was officially adopted in 1954.
Amhrán na bhFiann/ The Soldiers Song
The first National Anthem in ASL (American Sign Language) took place at Super Bowl XXVI. Harry Connick, Jr sang the National Anthem while Lori Hilary performed the Anthem in ASL.
The harp.
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