Oates, Titus 359
Obama, Barack 403
Obote, Milton 552
O’Brien, Richard 559
Observant Franciscans 241
Occam’s Razor 179
see also William of Ockham
Occasional Conformity Act (1711) 376, 382
repeal of (1719) 391
O’Connell, Daniel 427, 448
Odo, Bishop of Lucca 167
Odo of Bayeux 95
Offa, king of Mercia 52, 55, 56, 57, 58–9
Office for the Dead 186
Olaf, St 77
Olaf Guthfrithson, king of Dublin 66, 67
Olaf Tryggvason 74–5
Old Pretender
see James Edward Stuart
Old Sarum 92, 94
Oldcastle, Sir John 228
Oldham, Joseph H. 508, 521, 525, 527
Olympic Games 499, 537, 553
Ombdurman, Battle of (1898) 497
OMF (missionary society) 592
O’Neill, Hugh, Earl of Tyrone 343
O’Neill, Owen Roe 343
Open Christian Brethren 554
Operation Mobilization 592
Oratorians 494
Ordgar of Devon 74
Ordinariate of Our Lady of Walsingham 572
Ordovices (tribe) 6
organs, church 145
Origen 3, 160, 161, 593
original sin, and the Pelagian controversy 16
Ormonde, Duke of 343
Orosius (Spanish priest) 16
Orthodox Church 230, 555, 572
Orwell, George 517, 526, 529
Osbert (Mercian nobleman) 59
Osborne, John, Look Back in Anger (1956) 545
Osmund, Bishop of Salisbury 151, 192
Osmund of Ely 592
Oswald, Archbishop of York 70, 73
Oswald, king of the Northumbrians 33, 36, 37, 54
Oswy, king of the Northumbrians 37, 38–9, 42, 52
Otto, Holy Roman Emperor 67
Owen, David 559
Owen, John 347, 348–9, 393, 517
Owen, Wilfred 515, 539
Oxfam 551
Oxford, Robert Harley, 1st Earl of 376, 377, 381
Oxford Conference of Life and Work (1937) 524
Oxford Group (Moral Re-Armament) 520
Oxford Movement (Tractarian Movement) 443–50, 469–70
Oxford University 153–4, 172–80, 228, 448