Alexandria (215) — the same event in Cassius Dio, Herodian, History of the Empire and Historia Augusta

Cassius Dio: Antoninus came to Alexandria, pretended to welcome the leading citizens who received him outside the city with a banquet, killed them…

What each source says

Cassius Dio, Roman History · AD 215 · Alexandria

Antoninus came to Alexandria, pretended to welcome the leading citizens who received him outside the city with a banquet, killed them, and then loosed the whole army on the city to massacre

So when he reached the suburbs, whither the leading citizens had come with certain mystic and sacred symbols, he first greeted them cordially, even making him…
Location: 78(77).22.2

Cassius Dio, Roman History · AD 215 · Alexandria

The massacre continued day and night across the city, and he hid the death toll from the Senate; foreigners and their attendants also fell and temples were plundered

he slaughtered so many persons that he did not even venture to say anything about their number,
Location: 78(77).22.3

Cassius Dio, Roman History · AD 215 · Alexandria

Antoninus directed the massacre from the Temple of Serapis and dedicated to the god the sword used to kill his brother; he abolished Alexandria's spectacles and common meals and divided the city with a cross wall

Next he abolished the spectacles and the public messes of the Alexandrians and ordered that Alexandria should be divided by a cross-wall and occupied by guards…
Location: 78(77).23.3

Herodian, History of the Empire · AD 215 · Alexandria

Caracalla gathers the young men on the pretext of a review, surrounds them with soldiers and massacres them. They are buried in heaps in pits, and blood stains the mouths of the Nile.

So vaft was the Havock, that the Blood ran in Rivulets along the Plain, and tinged the Mouths of the Nile, tho* exceeding wide, and the adjacent Shores, with a…
Location: 4.9

Historia Augusta · AD 215 · Alexandria

He orders soldiers to kill their hosts, causing a great massacre in Alexandria

eos autem quos legerat occidit exemplo Ptolemaei Euergetis qui octavus hoc nomine appellatus est. dato praeterea signo militibus, ut hospites suos occiderent…
Location: Carac. 6.3

Where the sources differ

A and B are two of the sources listed above.

On what pointSource ASource BWhat differs (in Korean)
WhoHerodian, History of the EmpireHistoria Augustaa는 젊은이들을 사열한다며 모아 학살, b는 숙주인을 죽이라 명함
OutcomeCassius Dio, Roman HistoryHistoria Augustaa는 사망자 수를 원로원에 숨김

Place: Alexandreia (이집트)

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