Industrialization
Economics
Transportation
100
Industrialization began with this island nation.
England, United Kingdom, etc.
100
This rigid social structure of ancient India that is outlawed today predetermined a person's social and economic role in society.
Caste system
100
This railroad skirted cities for the most part and went across Russia.
Trans-Siberian Railroad
200
This person is widely known as the inventor of the steam engine.
James Watt
200
Merchants traveled this system of caravan routes across Central Aisa while importing silk and porcelain to Europe.
Silk Road
200
This infrastructure built by Romans transported water to their homes in their cities and still stands to this day in some places.
Aqueducts
300
This union was founded in 1905 so workers could gain some power over their own working conditions.
I.W.W. / Industrial Workers of the World
300
This modern-day country was the setting for the invention of paper, the compass, gunpower and the printing press.
China
300
On this Silk Road, those that road camels stopped at these types of inns. 
Caravanserai
400
Identify an ingredient that would be put into a blast furnace (described below).
400
In the end, this economic collapse brought on by deserted fields and deserted stock markets was not enough to keep the American people down for good.
Great Depression
400
This innovation in naval travel had triangular, or lateen, sails, which allowed ships to sail into the wind.
Caravel
500
This person invented the steam locomotive.
Richard Trevithick
500
This government common during the Medieval time period was based upon rulers granting land to those individuals that provided exemplary military service. Those without such luck tilled the land.
Feudalism
500
This historical development led to these crops traveling the world.
Columbian Exchange