I. It is unnecessary to stress the immense importance of developments in Christianity during the lifetime of Marcus. Justice cannot be done to such a subject here. All that is intended is a summary – difficult though even that is – of the main features, in particular of chronological problems. The status of Christians was definitively established (whatever had been the case earlier) by Trajan’s rescript to Pliny nine or ten years before Marcus’ birth. During the remainder of the second century Christian literature proliferated, and a good deal of it has survived. The first Apologists belong to the 120s or 130s. Major heretics – Marcion, Valentinus, Basilides, Montanus – were at work, provoking vigorous reaction and response. The earliest authentic accounts of ‘trials’ (the word may perhaps be misleading) and martyrdoms belong to the 150s; others, among the most important in the history of the early churches, survive from the 160s and 170s. Pliny’s letter is the earliest surviving ‘pagan’ record. The account of the Rome Christians’ savage execution by Nero was written by Pliny’s friend Tacitus a few years later (Ann. 15.44; perhaps c. 118); likewise, early in Hadrian’s reign, Pliny’s former protégé Suetonius briefly alluded to their execution (Nero 16.2). All three regarded Christians as pernicious and deserving death. There is a variety of comment in the later literature of the second century: a faint (and disputed) reference in Arrian’s Discourses of Epictetus; possible allusions in Apuleius; a fragment from a speech of Fronto, retailing the standard charges of cannibalism and incest; an amusing vignette by Lucian of a bogus Christian, Peregrinus (and a useful indication of hostility towards Christians by Alexander the false prophet of Abonutichus) (Pereg. 11-14; Alex. 25; 38); four comments by Galen (R. Walzer, Galen on Jews and Christians (1949) 14 f.); the full-scale attack by a man called Celsus; and a brief comment by Marcus himself in his Meditations (cf. below).