Federal policy began to drift from tribal termination during the late 1950s. Navajo Nation citizens Paul and Lorena Williams argued they could not be sued in state court for events arising in Indian country, and the United States Supreme Court agreed in 1959, ruling state jurisdiction would infringe upon tribes’ ability to self-govern. The Supreme Court’s decision reinvigorated tribal sovereignty, and the Miccosukee leader Mostaki, better known as “Buffalo Tiger,” pushed the limits of tribal sovereignty. When the United States refused to recognize the Miccosukee as an Indian tribe, Buffalo Tiger led a Miccosukee delegation to Fidel Castro’s Cuba in 1959. Castro acknowledged the Miccosukee as an Indian tribe, and the United States was forced to do the same upon Miccosukee’s return. President Lyndon Johnson took an interest in Indian affairs and passed the controversial Indian Civil Rights Act of 1968. However, President Richard Nixon became tribes’ greatest advocate. In 1970, he formally ended the termination era and set in motion policies that would lead to the present tribal self-determination era.