Uganda's official languages is English mainly because the country was a former British colony. The country has a cultural contrast of over 50 tribes and almost each speaks a different language. Communication is difficult at times even between countrymen. Fortunately English is widely spoken, except in remote, rural areas. It helps to have a local guide that understands the language of people from a particular area.
For non-English speakers, there are translators for a number of languages including Spanish, German, French, Italian, and Chinese among others. You could contact language centers such as the Makerere Institute of Languages, that have records of translators for particular languages.
Luganda and Swahiri languages are widely spoken in uganda. Offcourse before and after the British colonial masters,Uganda received the arab traders from the coast line who introduced the swahiri langauage among the locals as it was a language used during trade.