1678 is a date in the 17th century AD.
A century is 100 years long.
every hundred years makes a century
If the question being asked means, "What unit of time is greater than a century?", then the correct answer is "A millennium; however, if the question being asked means, "What comes after a century?", then the correct answer is "Another century."
Since a century is 100 years, half a century would be 50. So, the answer is 50 years.
William the Conqueror
The Age of the Vikings started somewhere between 700ad and 800ad in Norway. Soon after that around 860ad Harold Fairhair united Norway into one kingdom. It ended in 1066ad after a great defeat at The Battle of Stamford which only 25 ships out of over 200 returned to Norway.
The Norman invasion of England in 1066 was led by William the Conqueror, the Duke of Normandy, who became King William I after his victory over the Saxons. He was commonly known before this, especially in France, as William the Bastard (Guillaume le Bâtard) on account of his illegitimate birth.
Millennium (1000 years)
18th century
Sixteenth century.
the 19th Century, the 18th Century, the 4th Century BC A century is 100 years
The Century - Century City - was created in 2009.
1873 was the 19th century (1800-1899).
1st century 1-100, 2nd century 101-200, 3rd century 201-300, 4th century 301-400, 5th century 401-500, 6th century 501-600, 7th century 601-700, 8th century 701-800, 9th century 801-900 10th century 901-1000, 11th century 1001-1100, 12th century 1101-1200, 13th century 1201-1300, 14th century 1301-1400, 15th century 1401-1500, 16th century 1501-1600, 17th century 1601-1700, 18th century 1701-1800, 19th century 1801-1900, 20th century 1901-2000, 21st century 2001-2100
The 20th century
We are in the 21st Century.