"World History" is the most common expressions.
"I have a 2-hour world history class today."
"Who is teaching your world history class?"
Or if you are talking specifically about people groups around the world you might call it "History of Civilization."
"Civilization" - This is the study of societies that are in an advanced state for their time in history.
"In this class, we will be discussing civilizations from 700 bc to 100 bc."
"My history of civilizations class is boring."
"World History"（世界史）が一番一般的な言葉でしょう。
"I have a 2-hour world history class today."（今日は２時間の世界史の授業があるよ。）
"Who is teaching your world history class?"
（世界史を教えている先生は誰？）
"History of Civilization"（人文史・文明史）は、世界中の人々に関する歴史のことを表します。
"Cizilazation"（文明）はその時代の中でも特に人々の発展が進んだ社会のことを意味します。
"In this class, we will be discussing civilizations from 700 bc to 100 bc."
（このクラスでは、紀元前700~100年代の文明について学習します。）
"My history of civilizations class is boring."
（私が受けている文明史のクラスはつまらない。）
The subject title of studying the period before present time, is known as 'history'. Of course there are many branches of history such as modern history, ancient history or medieval history, national history, European history etc
"History is my favourite subject."
現代より前の時代を学習する科目を"history"（歴史）と言います。
歴史の中でも、近代史、古代史、中世史、国史、ヨーロッパ史などいろいろな分野があります。
"History is my favourite subject."
（歴史は私の好きな科目です。）
The main term would be 'World History', because the word 'world' denotes that it is the history of the whole planet and not just for one country. You can then separate world history into different time periods, for example: Modern history (recent history), Ancient history (history predating modern times), Prehistory (history before the ancient era, that is generally defined as the period of time before man began writing and recording history and manipulating metal).
World History' would be the most common name for this subject.You could also say 'Global History' and have it understood. Either of these subjects are what you are looking for as its title is self- explanatory .
In English, we regard the study of the history of the world to simply be "World History." It could be further divided into the timeframes of ancient (usually from prehistory to about 500 AD), medieval (500-1400 AD) and the modern ages (from the Renaissance onwards) (1400 to present)
こんにちは。
「世界史」は英語で world history と言うことができます。
例えば他に「アメリカの歴史」は US history や history of the United States などと表現できます。
下記は例文ですのでぜひ参考にしてください。
・I am interested in world history.
私は世界史に興味があります。
ぜひ参考にしてください。
イギリス 
日本 
アメリカ合衆国 
カナダ 
