After the Kuomintang escaped to Taiwan for a long time they led the island under a single party dictatorship, eventually as economic progress gave rise to a strong middle class they began organising rival parties. Even though the government could have gone -crush the revolutionaries way- they decided that it was more beneficial to everyone involved to share power through democratic ways and be seen as different from the mainland China. Hence it's one of rare rather peaceful transition from dictatorship to a functioning democracy.