Its initial leading members were Roger Makasa, ex-chairman of Uganda's Coffee Marketing Board, Robert Serumaga, a Ugandan playwright, and Andrew Adimola, who had formerly served as a minister in Amin's government.

[1] The opposition group attempted to hire Bolka Bar-Lev, an Israel Defense Forces colonel and mercenary, to murder Amin.

The Israeli concluded that he would have to raise a commando unit of 200–300 mercenaries (dubbed the "Equatorial Brigade") for the assassination plan, and demanded $1.5 million in advance.

[1] UNO ultimately raised $50,000 in advance payments and also covered the expensive hotel bills of Bar-Lev as well as his companions, but the Israeli colonel never actually delivered on his promises, and simply pocketed the money.

[5] In contrast, UNO joined a conference at Dar es Salaam, organized by Tanzanian President Julius Nyerere, to discuss a strategy to overthrow Amin.

[6] Despite its internal splits, UNO consequently recruited 50 militants who joined an exiled Ugandan rebel force that was trained to assist the Tanzanians against Amin's Uganda Army.

[1] The UNO fighters and other insurgents were put through a military "crash course" by the Tanzania People's Defence Force (TPDF) at a training camp located at Tarime.

When Lule was removed from office amid general political turmoil and replaced by Godfrey Binaisa, Serumaga went back into exile.