One thing appears to be common through centuries - victorious troops plundered their conquered lands - mainly for gold - for its value, transportability and ease of resale..right upto the last century.
read on about yamshita's gold.
Yamashita's Gold is the name given to the loot worth tens of billions of dollars stolen in Southeast Asia by Japanese forces during World War II and hidden in caves, tunnels and underground complexes in The Philippines.
The "gold" reportedly included many different kinds of valuables looted from banks, depositories, temples, churches, other commercial premises, mosques, museums and private homes. It takes its name from General Yamashita Tomoyuki, who assumed command of Japanese forces in the Philippines in 1944.
According to various accounts, the loot was initially concentrated in Singapore, from where it was later relayed to the Philippines.The Japanese hoped to ship the treasure from the Philippines to the Japanese home islands after the war ended