2000 Co-operative Wholesale Society merges with Co-operative Retail Services and the Co-operative Group is created. The group structure is agreed.

2007 Co-op Group merges with its biggest cooperative rival, United Co-operative. United’s ambitious boss Peter Marks becomes chief executive of the new merged organisation.

2009 Co-op pays £1.6bn to take over Somerfield supermarket chain. The Co-operative Bank and Britannia building society agree a merger, under Neville Richardson.

July 2011 Richardson quits with £4.6m, following a restructuring that sheds 670 financial adviser jobs. Barry Tootell takes over.

August The Co-operative Group announces a bid for 632 Lloyds branches, Project Verde.

December Lloyds board approves the Co-op bid. Privately, City regulator warns Lloyds that Co-op lacks the reserves to underwrite the deal.

March 2013 Co-op Bank blames Britannia for a £257m loss in 2012. Co-op’s insurance and asset management businesses are lined up for sale.

April Co-op withdraws offer for Lloyds branches, blaming the economy and “regulatory requirements”.

May Moody’s downgrades the bank’s credit rating to junk and Tootell resigns. B&Q boss Euan Sutherland becomes chief executive of the Co-operative Group and axes the Rev Paul Flowers, chairman of the Co-op Bank.

June Co-op Bank reveals a £1.5bn black hole in its reserves.

October Co-op hands bondholders control of the bank to seal a rescue. Co-op left with 30% stake.

6 November Flowers is questioned by Treasury select committee about Lloyds deal, shows limited grasp.

17 November The Mail on Sunday publishes a video showing Flowers arranging to buy drugs.

12 December Co-op Group hires former City minister Lord Myners to review its operations for £1 salary.

11 March 2014 Co-op Group CEO Sutherland resigns after £6.6m pay deal is leaked to the Observer. He brands the Co-op “ungovernable”.

14 March Myners warns that the Co-op Group could go bust unless it urgently reforms its board and voting structure. He outlines a plan to replace its multilayered hierarchy with a plc-type board. Faces “bullying” tactics from Co-op activists.

24 March Co-op Bank reveals losses for 2013 could be as high as £1.3bn.

7 April Co-op Bank delays full-year financial results until 11 April.

9 April Myners quits over increasing opposition to his plans. He will, however, complete his review.

17 April Co-op reveals losses of £2.5bn after the most “disastrous year” in the mutual’s 150-year history.

7 May Myners calls for radical overhaul of Co-op Group. Flowers pleads guilty to drug charges.

9 May Co-op’s stake in banking arm expected to shrink to 20% after rescue fundraising, which saw US hedge funds take control of the bank

29 May Co-op says it will put reforms of its governance to a vote in September after consulting with its regional boards and independent societies.

18 July Co-op sells pharmacies to Bestway in £620m deal

4 August Co-op sells farms business to Wellcome Trust for £249m

8 August Co-op sets out radical plans for shake-up in how it is run

30 August Co-op members back radical shakeup to ‘rebuild business’

1 October Eleven directors leave Co-op board as reforms begin

19 February 2015 Former Asda and Royal Mail boss Allan Leighton becomes the society’s first independent non-executive chair under its reformed structure. He will oversee the overhaul of the board.

27 March Co-op Bank chief executive Niall Booker is handed a potential £5m pay deal, sparking a row as he prepares to axe more jobs and close another swath of branches. Losses more than halved in 2014.

3 April Co-op’s board prepares to take a historic step back from direct involvement in politics with a decision not to endorse up to £1m of donations to the Co-operative party, which is affiliated to the Labour party.

9 April Co-op boss Richard Pennycook hails end of rescue phase as the group returns to profit and cuts debt.