1952 - Eritrea, a former Italian colony and U.N.-mandated territory since World War Two, is federated with Ethiopia under Emperor Haile Selassie

1962 - Eritrea becomes province of Ethiopia, fuelling independence struggle

1975 - After ousting of Selassie, Lt-Col Mengistu Haile Mariam emerges as leader of Dergue Marxist regime in Ethiopia. In following years, thousands of suspected opponents killed in "Red Terror" campaign

1984-5 - Famine in Ethiopia claims around 1 million lives. Throughout 1980s, rebel groups fight for independence in Eritrea and northern Ethiopian province of Tigray

1991 - Eritrean rebels enter Asmara. Days later, Ethiopian and Eritrean rebels seize Addis Ababa. Mengistu flees

1993- Eritrea gains independence after referendum. Eritrea enjoys good relations with Ethiopia

1997
Ethiopian troops temporarily occupy Eritrean territory around area of Bada in Eastern Eritrea. Eritrea introduces own currency. Attempts to regulate cross-border trade lead to disagreement over where border lies

1998

May - Start of border war. Eritrean and Ethiopian troops clash in western border region of Badme

Jun - Ethiopia accepts peace plan drawn up by United States and Rwanda, requiring Eritrea to withdraw to pre-May positions

Nov - Ethiopia accepts Organisation of African Unity (OAU) peace plan but Eritrea objects to certain elements. Talks fail

1999

Feb-Mar - Second offensive. Ethiopia counter-attack wins back territory, including Badme, after days of trench warfare with loss of thousands of lives

2000

May-Jun - Third offensive. Ethiopia makes more gains, including in regions of Debub and Gash Barka, which account for 80 percent of Eritrean food production

May - U.N. Security Council votes for arms embargo against both sides in punishment for renewing war. Ethiopian Prime Minister Meles Zenawi declares border war ended

Jun - Both sides agree to ceasefire

Dec - Peace agreement brokered by OAU is signed in Algiers. Plan calls for deployment of U.N. peacekeeping force in 25-km (15-mile) buffer zone. As part of agreement, independent boundary commission set up to decide on exact location of border based on past colonial treaties. Ethiopia and Eritrea agree to accept commission's decision with no right of appeal

2001

Jan - U.N. peacekeeping force deployed to monitor peace

2002

Apr - Hague-based Eritrea-Ethiopia Boundary Commission (EEBC) delivers ruling on border but fails to delineate disputed town of Badme

2003

Mar - EEBC rules Badme is in Eritrea. Ethiopia rejects ruling

Nov - Ethiopia accepts ruling "in principle" but wants dialogue with Eritrea first, which Eritrea refuses

2005

Sep - Eritrea warns it might restart war with Ethiopia if U.N. fails to resolve dispute over Badme

Oct - Eritrea bans U.N. helicopters from its airspace, forcing closure of several U.N. bases along border

Nov - U.N. peacekeepers say both Ethiopia and Eritrea moved troops and tanks towards border. Security Council threatens sanctions on both nations if they fail to step back

Dec - Eritrea orders U.N. peacekeepers from Western countries to leave. Security Council agrees to pull out U.S., Canadian and European peacekeepers from Eritrea and relocate them "temporarily" in Ethiopia

2006

Jan - Ethiopia complies with U.N. demand to withdraw troops from border. Eritrea refuses to lift restrictions on U.N. peacekeepers

Jan - U.S. and Eritrean officials hold talks in Washington over border crisis, but Eritrea blocks U.S. mediator Jendayi Frazer from travelling to Eritrean side of border

Mar - Boundary Commission organises talks between Ethiopia and Eritrea. U.S. and U.N. also present. Both parties agree to resume demarcation process

Jun - Security Council votes to trim peacekeeping force in border area to 2,300 troops from 3,300, after two countries fail to meet council demands to accept shared border drawn by international experts and end all restrictions on peacekeeping operations

Oct - Eritrea moves troops and tanks into U.N. buffer zone, prompting U.N. to accuse it of breaching peace accord. Eritrea says troops are there to work on development projects

Nov - Both sides reject proposal from U.N.-appointed panel to demarcate border on maps, leaving the two states to establish physical boundary themselves

2007

Jan - U.N. chief issues report warning stalemate on border issue threatens regional security and could trigger renewed conflict

Security Council slashes peacekeeping force to 1,700 troops

Feb - Ethiopia says foils Eritrean-backed attack targeting African Union summit in Addis Ababa. Asmara denies accusation

Jun - Ethiopia writes to Security Council indicating its acceptance of boundary ruling. Asmara dismisses announcement, saying attached conditions mean Ethiopia doesn't intend to comply fully

Sep - Boundary commission brings two sides together for talks aimed at physically demarcating border, but no progress made

Nov - Eritrea accuses Ethiopia of planning invasion. Accusation denied by Addis Ababa

Boundary commission leaves frontiers as demarcated on Ethiopia's and Eritrea's maps. Eritrea accepts ruling but Ethiopia rejects it

Dec - Eritrea cuts off fuel supplies to U.N. peace force on border, hampering operations

2008

Jan - Security Council renews mandate of U.N. force for six months

Feb - Eritrea cuts off food supplies to U.N. troops and stops them withdrawing to Ethiopia. Peacekeepers regroup in Asmara. U.N. Security Council condemns "systematic violations" of its resolutions

Mar - Report by U.N. Secretary-General Ban Ki-moon urges Security Council to take up Eritrea-Ethiopia dispute, warning it could escalate if left unresolved