Simplify the following text for a Grade 10 native English-speaking person.
Original: At the 1969 elections , again with Brandt as the leading candidate , the SPD became stronger , and after three weeks of negotiations , the SPD formed a coalition government with the smaller Free Democratic Party of Germany ( FDP ) .
Simplified: He started the social-liberal coalition between the SPD and the Free Democratic Party of Germany ( FDP ) . Willy Brandt became Chancellor in 1969 .