Japan is an island nation with no major railroads attach to other countries, therefore they rely on merchant shipping. Also Japan has limited Natural Resources and relies on imports from other countries, which requires a large merchant fleet.
Greece has the largest merchant fleet in the world. Here are the facts:RankCountryNo.DwtNo.DwtNo.DwtNo.DwtNo.Dwt1Greece78061,9951,32974,9671505,0896506,6872,909148,7382Japan76837,13785551,7262157,2218377,8012,675103,8863Norway47933,36117911,078185344736,4301,14951,4034United States41733,2711146,010832,8503764,72299046,8535China3167,50159524,8682184,7189497,8282,07844,9156Germany1967,3881576,71083022,5758876,2072,07042,8807Hong Kong13716,04222516,612361,2871171,73251535,6738Korea (South)2238,24218013,157962,2902611,54176025,2309Taiwan423,23217411,4131916,72010985051622,21510United Kingdom1597,648776,8191245,2952462,14560621,90711Singapore30911,6621194,9811423,0441281,11369820,80012Denmark1497,122221,4141306,5252261,24352716,30413Russia3867,5641161,873327461,1094,3911,64314,57414Saudi Arabia7711,02412168163049511,39815Italy2274,883543,585122981512,19344410,95916India1136,3401004,0763875025426610,75717Turkey931,3181405,349353842721,7315408,78218Iran355,459442,0087179386821248,32919Switzerland361,313321,429893,403748882317,03320Malaysia942,809582,54136784885312766,664All Other Countries2,28666,0991,22651,00953813,2725,52332,9229,573163,302Total7,322341,4095,797301,6282,98687,36912,58092,19528,685822,601
Norway
The Dutch Merchant fleet was the biggest in the world from 1600 till 1750. After that the English became the leading country.
Greece
Coke has the largest fleet in the "world" walmart is large, but not even the largest in the US walmart of course
Germany used their subs for "Guerre de Course"-Merchant Ship destruction (Commerce Raiding). Japan used their subs for "Guerre de Escadre"-Fleet Warfare US-the USN sub force was powerful enough to use both types of "Guerre"s-Fleet and Merchant warfare.
BRAZIL
5 largest in japan
Japan is very developed as it has the third largest economy in the world.
Norway
Norway
In 2014, the largest population city in the world was Tokyo, Japan. It had an estimated population of over 37 million people.