At the end of the ninth century in Bohemia, the Przemyslid family succeeded in laying the foundations of a Czech state. They did this by ridding themselves of all of the things that were standing in their way, like the Slavnik clan - which the Przemyslids murdered in a particularly bloody manner. You needn't feel too bad for the Slavnik clan, though, as they'd gotten rid of their rivals in the Vrsovec clan using very similar methods just a little while before.
Plowman tells it differently, of course.
The Przemyslid rulers were a mixed bag, at least at the start of their reign in Bohemia. Wenceslas I, the fourth Przemyslid Czech ruler, was made a saint soon after his murder in 929 or 935. Boleslav was a pagan, and he felt that Wenceslas was frittering away too much time with this new Christian fashion he'd picked up and also didn't like the alliance his brother had entered into with Saxony. The Przemyslids are remembered well in the Czech Republic today, though, as most people are not aware of the family's murderous streak. Well, the power of Bohemia under the Przemyslid dynasty increased, prompting expansionist ambitions typical of the early feudal empires.