February 1st to 7th

~ from a post on the United Nations website

World Interfaith Harmony Week is an annual event observed during the first week of February, after General Assembly designation in 2010.  The General Assembly pointed out that mutual understanding and interreligious dialogue constitute important dimensions of a culture of peace and established World Interfaith Harmony Week as a way to promote harmony between all people regardless of their faith.

Recognizing the imperative need for dialogue among different faiths and religions to enhance mutual understanding, harmony and cooperation among people, the General Assembly encourages all States to spread the message of interfaith harmony and goodwill in the world’s churches, mosques, synagogues, temples and other places of worship during that week, on a voluntary basis and according to their own religious traditions or convictions.

For more information see this United Nations website page and the World Interfaith Harmony Week website.