taekwondo1-6, Exercise 1: Overseas strands

Model answer:

Jhoon Rhee: in 1962, after college in Texas, he opened a chain of schools in the Washington, D.C. area practising Traditional Taekwondo; in the 1970s, at Choi Hong-hi's urging, he adopted ITF-style Taekwon-Do, later left the ITF over the political controversies around Choi, and developed Jhoon Rhee-style Taekwondo, mixing traditional and ITF elements with original ones. His own article calls him the "father of American taekwondo" (a title with an owner).
ATA: in 1969 Haeng Ung Lee, a former South Korean military instructor, moved to Omaha, Nebraska and founded a chain of schools; the style is Songahm Taekwondo; it became one of the largest chains in the United States; its international spin-offs were reunited as ATA International in 2015.
ITF side: ITF organisations credit Choi with starting the international spread by stationing Korean instructors around the world (Choi Hong-hi article).

What the sources do not say: any country-by-country account of the spread in Europe, Latin America, Africa or Asia beyond Korea; these are gaps, not facts to fill from memory.

Sources: Wikipedia, Taekwondo; Jhoon Rhee; Choi Hong-hi; International Taekwon-Do Federation.