Tools of the HistorianTools of the Historian

Measuring and Organizing Measuring and Organizing

TIMETIME

How Do We MEASURE How Do We MEASURE Time?Time?

To study the past, historians To study the past, historians must have a way to identify must have a way to identify and describe when things and describe when things happened. happened.

They do that by measuring They do that by measuring and labeling time in different and labeling time in different ways.ways.

CalendarsCalendars

We rely on calendars, or We rely on calendars, or dating systems, to measure dating systems, to measure time.time.

A calendar arranges days in A calendar arranges days in order.order.

Cultures throughout the world have Cultures throughout the world have developed different calendars developed different calendars based on important events.based on important events.

AztecAztec

CalendarCalendar Mesopotamian Mesopotamian

CalendarCalendar

Ancient Egyptian Ancient Egyptian CalendarCalendar GreekGreek

CalendarCalendar

CalendarsCalendars Different cultures in the world have developed about 40 different calendars.Different cultures in the world have developed about 40 different calendars. Some cultures developed Some cultures developed

calendars based on nature, calendars based on nature,

such as the cycle of the such as the cycle of the

moon.moon. The Chinese, Jewish and The Chinese, Jewish and

ancient Egyptians are someancient Egyptians are some

of these cultures.of these cultures.

Calendars: many are based on Calendars: many are based on events of religious importance events of religious importance

Christian Christian

CalendarCalendar

birth of birth of

JesusJesus

Jewish = 3,760 years Jewish = 3,760 years before the Christian before the Christian when they believe the when they believe the world was created world was created

Muslims = begin with the time Muslims = begin with the time

when their leader, Muhammad, when their leader, Muhammad,

left the city of Makah for Medina; left the city of Makah for Medina;

622 years after the birth of Christ622 years after the birth of Christ

What calendar do we use?What calendar do we use?The calendar we use today is The calendar we use today is

based in part on a calendar based in part on a calendar developed by Julius Caesar a developed by Julius Caesar a Roman leader. The calendar is Roman leader. The calendar is called the Julian calendar. called the Julian calendar. (365.25 days/year with a leap (365.25 days/year with a leap year every 4year every 4thth year). year).

It was revised in 1582 by Pope It was revised in 1582 by Pope Gregory XIII to start counting Gregory XIII to start counting with the birth of Jesus Christ.with the birth of Jesus Christ.

We use this Calendar as does most of the world.

What Calendar do we use in What Calendar do we use in today in the United States?today in the United States?

Answer on your white boardAnswer on your white board

Why are calendars different Why are calendars different from culture to culture?from culture to culture?

Answer on your white board…Answer on your white board…

Dating EventsDating Events The years before the birth of Jesus The years before the birth of Jesus

are known as are known as ““B.C.B.C.”” or before Christ. or before Christ. (To avoid religious references in dating (To avoid religious references in dating

many historians prefer B.C.E. many historians prefer B.C.E. ““before before current eracurrent era””))

The years after are called A.D. or The years after are called A.D. or ““anno Dominianno Domini”” a Latin phrase for a Latin phrase for ““in in the year of our Lord.the year of our Lord.”” (Current books are beginning to use C.E. (Current books are beginning to use C.E.

““current eracurrent era””))

Dating EventsDating Events

To date events To date events beforebefore the birth of Christ, or the birth of Christ, or B.C., we count backwards from A.D. 1. B.C., we count backwards from A.D. 1.

There is no year There is no year ““00”” The year before A.D. 1 The year before A.D. 1 is 1 B.C. is 1 B.C. (Notice that (Notice that ““A.D.A.D.”” is written before the date, is written before the date,

while while ““B.C.B.C.”” is written following the date.) is written following the date.) We often times leave A.D. out all together, so if We often times leave A.D. out all together, so if

a date is shown with neither A.D. or B.C. we a date is shown with neither A.D. or B.C. we assume that it is A.D.assume that it is A.D.

To date events after the birth of Christ, or To date events after the birth of Christ, or ““A.D.,A.D.,”” we count forward, starting at A.D. 1. we count forward, starting at A.D. 1.

What do What do ““B.C.B.C.”” and and ““A.D.A.D.”” mean? mean?

Answer on your white board…Answer on your white board…

What year came after What year came after 184 B.C.?184 B.C.?

Answer on your white board…Answer on your white board…

What do “B.C.E.” and “C.E.” What do “B.C.E.” and “C.E.” mean?mean?

Answer on your whiteboardAnswer on your whiteboard

How do we How do we ORGANIZE Time?ORGANIZE Time?

One way to measure and One way to measure and organize time is to label organize time is to label groups of years. Dividing it groups of years. Dividing it into blocks of time.into blocks of time. For example, a group of 10 For example, a group of 10

years is called…years is called… a decade.a decade.

Periods of HistoryPeriods of History

Historians divide history into blocks Historians divide history into blocks of time known as periods or eras.of time known as periods or eras. A period of 10 years = decadeA period of 10 years = decade A period of 100 years = centuryA period of 100 years = century A period of ten centuries = MillenniumA period of ten centuries = Millennium

Periods of HistoryPeriods of History

Centuries are grouped into even longer time Centuries are grouped into even longer time periods known as eras, which are given names.periods known as eras, which are given names.

Prehistory is the first of these long periodsPrehistory is the first of these long periods Prehistory: the time before people developed Prehistory: the time before people developed

writing (beginning – 5,500 years ago)writing (beginning – 5,500 years ago) Ancient History: ending c. A.D. 500 (c., or Ancient History: ending c. A.D. 500 (c., or

circa, means circa, means ““aboutabout””).). Middle Ages (medieval period): the next Middle Ages (medieval period): the next

thousand years c. A.D. 500 – c. A.D. 1500thousand years c. A.D. 500 – c. A.D. 1500 Modern History begins from c. A.D. 1500 and Modern History begins from c. A.D. 1500 and

continues to the present day.continues to the present day.

When Did It Happen?When Did It Happen?

One way historians tell or write a One way historians tell or write a story of the past is to put the story of the past is to put the events in the order in which they events in the order in which they happened. happened. Time order is called Time order is called chronology.chronology.

What root words do you see in What root words do you see in chronology?chronology?

Time Lines : Tools to help you Time Lines : Tools to help you Organize Time!Organize Time!

A time line is another way to track the passage of time.A time line is another way to track the passage of time. A time line is a diagram that shows chronological events or A time line is a diagram that shows chronological events or

order of events within a period.order of events within a period. Most time lines are divided into sections in which the Most time lines are divided into sections in which the

sections are evenly spaced.sections are evenly spaced. Events are placed on a time line at the date when the Events are placed on a time line at the date when the

event occurred.event occurred.

TimelinesTimelines Sometimes the Sometimes the

spread of time may spread of time may be too long to show be too long to show all the years in even all the years in even spaces. spaces.

To save space, a To save space, a period of time may period of time may be omitted or left out be omitted or left out from the time line. from the time line.

Where this happens, Where this happens, a slanted or jagged a slanted or jagged line appears on the line appears on the time line to show a time line to show a break in the even break in the even spacing of events.spacing of events.

There are different types of time There are different types of time lines: lines:

It is your turn!It is your turn! Remember our Social Studies theme?Remember our Social Studies theme?

Continuity and ChangeContinuity and Change You will create a timeline of your life You will create a timeline of your life

that highlights the changes that have that highlights the changes that have taken place.taken place.

On the back you will make a list of On the back you will make a list of three things that have continuity. three things that have continuity. You may want to discuss this with your family and You may want to discuss this with your family and

see what is the same today as it was for them in see what is the same today as it was for them in the past. the past.