11 events the sources record for this year, grouped by region.
What happened
China (6)
Cao Cao advanced to Ruxu Mouth, broke Sun Quan's camp west of the river, captured Gongsun Yang, and then withdrew. (Records of the Three Kingdoms (Sanguozhi) 魏書 武帝紀 (卷01) 建安18년)
The emperor invested Cao Cao as Duke of Wei, enfeoffed him with ten commanderies of Jizhou, and granted him the Nine Bestowals. (Records of the Three Kingdoms (Sanguozhi) 魏書 武帝紀 (卷01) 建安18년)
Li Yan of Liu Zhang's side led the troops of Mianzhu and surrendered to Liu Bei; Liu Bei besieged Luo. (Records of the Three Kingdoms (Sanguozhi) 蜀書 先主傳 (卷32) 建安18년)
Cao Cao attacked Ruxu, but Sun Quan held out for a little over a month; when Cao Cao saw that his army was well ordered, he withdrew. (Records of the Three Kingdoms (Sanguozhi) 吳書 吳主傳 (卷47) 建安18년)
In the first month Cao Cao advanced to Ruxukou, broke Sun Quan's Jiangxi camp, and captured the commander Gongsun Yang. Sun Quan held out with seventy thousand men, and when the two sides faced each other for over a month, Cao Cao looked at the boats and armor and sighed, 'If one begets a son, he should be like Sun Zhongmou.' (Zizhi Tongjian (Comprehensive Mirror) 資治通鑑 卷066 (원문 단락 #5356, 213년))
In the ninth month Yang Fu and Jiang Xu entered Lucheng, and Yang Ang and Chen Feng relied on Qishan to subdue Ma Chao. When Ma Chao, on Zu's stratagem, sortied, the gates of Qi city closed and he lost his wife and children, so he attacked Yicheng and seized Jiang Xu's mother. (Zizhi Tongjian (Comprehensive Mirror) 資治通鑑 卷066 (원문 단락 #5366, 213년))
Southern Europe (4)
Campaign against the Alamanni: he ordered forts and cities founded in his own name wherever he liked, and massacred young men conscripted as mercenaries by surrounding them on a shield signal (Cassius Dio, Roman History 78(77).13.4)
War with the Germanic Cenni: captured women killed themselves when sold, and killed their children; the Cenni accepted defeat for a large sum (Cassius Dio, Roman History 78(77).14.1)
Preparing an Eastern campaign, he breaks off and stays in Dacia; in Raetia he kills a number of natives and gives the soldiers a donative (Historia Augusta Carac. 5.4)
After defeating the Germans, he takes the title 'Germanicus' (Historia Augusta Carac. 5.6)
Eastern Europe & Russia (1)
Caracalla leaves for the Danube, eats simply like a soldier and mostly marches on foot. (Herodian, History of the Empire 4.7)