In 1596 the Polish king decided to move the capital from Krakow to Warsaw, making Warsaw the most important city in Poland.
the capital of poland was once Krakow
( z1 city :name ( z2 name :op "Krakow" ) :ARG0-of ( z3 have-org-role :ARG1 ( z4 country :name ( z5 name :op "Poland" ) ) :ARG2 ( z6 capital ) :time ( z7 once ) ) )