Complex sentence: Kingston achieved prominence in 1998 when she led a sit-in of journalists at the federal election campaign launch of the One Nation Party in the Queensland town of Gatton--the journalists were unhappy with the party's treatment of the media during the campaign.
Split into simpler sentences: Kingston achieved prominence in 1998 when she led a sit-in of journalists at the federal election campaign launch of the One Nation Party in the Queensland town of Gatton. The journalists were protesting the party's treatment of the media during the campaign.