Citizens in the nation and other parts of the world took a break at 1 p.m. Kenyan time (5 a.m. ET) to collectively sing the hymn.
Drivers pulled over on the side of the roads while crowds gathered at malls and busy intersections to sing the anthem. The singing drifted over the bustling capital of Nairobi, where lunchtime rush hour noise includes honking car horns and loud music blaring from stores.
Organizers said the grassroots effort is aimed at promoting unity in the east African nation, where ethnic violence left more than 1,000 people dead after disputed elections four years ago.
"The whole point is to unite Kenyans in one action and provoke reflection about personal responsibility," said organizer Al Kags.
"We decided to go with the national anthem because it is the main prayer that binds us together. It's a clarion call that transcends all boundaries -- physical, mental, tribal, you name it.".