Watch part two
The Crimean Peninsula was once part of Russia, but in 1954 in a gesture to mark 300 years of supposedly indivisible union, Nikita Khrushchev, the then Soviet premier, transferred it to the Ukraine.
When the USSR broke apart in 1991, the newly independent Republic of Ukraine kept the Crimea and the strategically important Black Sea port of Sevastopol.
The Russian navy meanwhile clung on to its naval base there.
In 1997, after years of tense negotiations, the two countries cemented this uneasy status quo in a 20 year agreement.
Viktor Yushchenko, Ukraine's president, has since aligned Ukraine with the West, infuriating Moscow and the one-third of the country's Russian-speaking residents.
Facing elections next January, Yushchenko has vowed not to renew the base agreement when it expires in 2017, a prospect that will leave Russia cut off from its only warm water port.
As Richard Setbon reports Russia and Ukraine are now on a collision course over the country's future, and Sevastopol with its Russian majority and Black Sea fleet is the flashpoint.
This episode of People & Power airs from Wednesday, October 14, 2009 at the following times GMT: Wednesday: 0600, 1230; Thursday: 0130, 1400, 1930; Friday: 0630, 1630; Saturday: 0330, 2030; Sunday: 0030, 0530; Monday: 0830.
Source: Al Jazeera