Yemen's warring parties agreed on Tuesday to renew until Oct. 2 a truce the United Nations says has brought the longest period of relative calm in over seven years. [L1N2ZE1Z5] Following is a timeline of Yemen's slide into conflict.
* 1990: Unification of north and south Yemen to form a single state under President Ali Abdullah Saleh.
* 1994: Civil war in which Saleh prevents south, angered by what it sees as its lower status, from splitting with north.
