<Tr> <Td> </Td> <Td> Communities become a pillar of the EU </Td> <Td> 1 November 1993 </Td> </Tr> <Tr> <Td> </Td> <Td> Pillar abolished </Td> <Td> 1 December 2009 </Td> </Tr> <Tr> <Td_colspan="2"> Currency </Td> <Td> 13 currencies (show) <Ul> <Li> EUA / ECU (accounting) </Li> <Li> Belgian franc </Li> <Li> Danish krone </Li> <Li> French franc </Li> <Li> German mark </Li> <Li> Greek drachma </Li> <Li> Irish pound </Li> <Li> Italian lira </Li> <Li> Luxembourgish franc </Li> <Li> Dutch guilder </Li> <Li> Portuguese escudo </Li> <Li> Spanish peseta </Li> <Li> Pound sterling </Li> </Ul> </Td> </Tr> <Ul> <Li> EUA / ECU (accounting) </Li> <Li> Belgian franc </Li> <Li> Danish krone </Li> <Li> French franc </Li> <Li> German mark </Li> <Li> Greek drachma </Li> <Li> Irish pound </Li> <Li> Italian lira </Li> <Li> Luxembourgish franc </Li> <Li> Dutch guilder </Li> <Li> Portuguese escudo </Li> <Li> Spanish peseta </Li> <Li> Pound sterling </Li> </Ul>

Why did european unity come in the form of an economic alliance