Mohammad-Reza Shajarian was an Iranian singer, Musician, and master of Persian traditional music. He was also known for his skills in Persian calligraphy and humanitarian activities. Shajarian started his singing career in 1959 at Radio Khorasan, rising to prominence in the 1960s with his distinct style of singing. His main teachers were Ahmad Ebadi, Esmaeil Mehrtash, Abdollah Davami, and Nour-Ali Boroumand. He also learned the vocal styles of singers from previous generations, including Reza Gholi Mirza Zelli, Fariborz Manouchehri, Ghamar Molouk Vaziri, Eghbal Azar, and Taj Isfahani. He has cited legendary Persian tar soloist Jalil Shahnaz as highly influential to his development, indicating that he has often tried to mimic Shahnaz's playing style in his singing. Shajarian had collaborated with musicians such as Parviz Meshkatian, Mohammad Reza Lotfi, Hossein Alizadeh, Faramarz Payvar, Dariush Pirniakan, and Sohrab Pournazeri. He was recognized as a skilled singer in the challenging traditional Dastgah style. In 1999, UNESCO in France presented him with the Picasso Award and in 2006 with the UNESCO Mozart Medal. In 2017, Los Angeles Times cited him as the "Greatest living maestro of Persian classical music". His works cover also some songs of Iranian ethnic music including Mazandarani music, Azeri music, Kurdish music and Lur music. After coming out in support of the Iranian Green Movement and criticizing the Iranian government, he was banned from holding concerts and releasing music.