The 20th century saw two devastating World Wars, the rise and fall of imperial powers, and the establishment of international organizations aimed at preventing future conflicts. World War I from 1914-1918 caused over 19 million deaths and led to the formation of the League of Nations. World War II from 1939-1945 was even more destructive, resulting in over 60 million deaths, and led to the United Nations being founded to replace the ineffective League of Nations. Both world wars established that collective security was needed to maintain peace.

3. The 20th century
was a century of growth and
development in areas of the economy,
technology and communications.
It was also the century of two World Wars and
the Cold War.

4. The same century that saw the
emergence of the League of Nations and
the 20th century was also the world's
bloodiest century.

7.  also known as the First World War or the Great War,
was a global war centered in Europe that began on 28 July
1914 and lasted until 11 November 1918.
 By the end of the war, four major imperial powers—the
German, Russian, Austro-Hungarian and Ottoman
empires—ceased to exist.

8.  Over 19 Million Deaths
 21 million wounded
 Cost 200 billion dollars
 Involved 17 nations

11. The League of Nations (abbreviated as LN
in English, "Société des Nations" abbreviated
as SDN in French) was an intergovernmental
organisation founded on 10 January 1920 as a
result of the Paris Peace Conference that ended
the First World War.

12. to maintain world peace.
preventing wars through collective
security and disarmament and settling
international disputes through
negotiation and arbitration

14. DISARMAMENT
Disarmament is the act of reducing, limiting, or
abolishing weapons. Disarmament generally
refers to a country's military or specific type of
weaponry. Disarmament is often taken to mean
total elimination of weapons of mass destruction,
such as nuclear arms.

15. Preventing War Through Collective
Security
Collective Security
 Collective security can be understood as a security
arrangement, political, regional, or global, in which
each state in the system accepts that the security of
one is the concern of all, and therefore commits to a
collective response to threats to, and breaches to
peace.

16. Settling Disputes Between Countries
Through Negotiation And diplomacy
 Before opening negotiations, be sure to have a plan for
yourself, as well as a plan for the power or powers with
whom you are negotiating.
 Without a plan, negotiation does nothing except
damage your reputation when you are unable to live up to
the promises you made.

18. Over 60 millions deaths
Over 80 million wounded
Cost 3.3 trillion dollars
Involved 61 nations
Most destructive war in the history

20. World War II (WWII or WW2), also known as the
Second World War, was a global war that lasted from 1939
to 1945, though related conflicts began earlier. It involved
the vast majority of the world's nations—including all of
the great powers—eventually forming two opposing
military alliances: the Allies and the Axis.

23. UNITED NATIONS
 The United Nations (UN) is an intergovernmental organization
established 24 October 1945, to promote international co-operation.
 replacement for the ineffective League of Nations, the
organization was created following the Second World War to prevent
another such conflict. At its founding, the UN had 51 member states;
there are now 193.

25. To save succeeding generations from the
scourge of war….
To reaffrim faith in Human rights
To establish conditions under which
justice can be maintained
To promote social progress and better
stnadards of life in larger freedom.