Philip II of Spain made serious efforts to raise revenue to fund his empire through taxation and loans, but it led to problems and was ultimately unsustainable. He imposed taxes that heavily burdened the lower classes and sold crown lands for short-term gain. Constant warfare drained the Spanish economy, and Philip's borrowing led to high interest rates and debt that foreign financiers could exploit. Spain faced bankruptcy multiple times, high inflation, declining population, weak agriculture and industry, and over-reliance on trade, laying the roots for its later economic and geopolitical decline.