Világ was a planet that had a single landmass. It was divided between three countries, the two largest being Galen and Malendia, both monarchies, with the third being Kozepén, a republic. Although the executive powers of the monarchies had become largely symbolic by the time the Sixth Doctor and Evelyn came there, the families of both countries were both revered and seen as "role models, if not policymakers" according to the Sixth Doctor. (AUDIO: Arrangements for War)
History
Galen and Malendia had been at war for a century or so. The Kingdom Alliance, the marriage between Krisztina, the Princess of Galen, and Viktor, Prince of Malendia, was intended to end it. There were some violent attacks from anti-Alliance factions, the worst being the attack on the Galen palace itself. (AUDIO: 'rrangements for War) War broke out again after it was revealed that Krisztina was still secretly in love with Reid.
The planet was invaded later by the Killorans. The inhabitants were able to defeat the invaders. It was visited by the Sixth Doctor and Evelyn weeks before the invasion, (AUDIO: Arrangements for War) who then returned a year later.
In the year after the invasion, the three countries had become unified, now called the Triumvirate, lead over by the Principal Triumvir; Justice Rossiter. Evelyn decided to stay and marry him. Two years later, the Doctor returned with Mel to check up on Evelyn. Unknown to Evelyn, she was the subject of experimentation with Killoran DNA. The Doctor managed to undo the damage done to her. While recovering, she was visited by the Seventh Doctor. (AUDIO: Thicker Than Water)
Flora and Fauna
Galen at least had fish, as well as Xenoblossoms, flowers which, when a wind blew across them, caused vibrations and harmonics, which could be hypnotic to older people such as Evelyn. (AUDIO: Arrangements for War)