Following Vladimir's death in 1015, Yaroslav waged a complicated war for the Kievan throne against his half-brother Sviatopolk, ultimately emerging victorious in 1019.

He successfully captured the area around present-day Tartu, Estonia, establishing the fort of Yuryev, and forced nearby regions to pay tribute.

He was a patron of literary culture, sponsoring the construction of Saint Sophia Cathedral in 1037 and promoting the first work of Old East Slavic literature by Hilarion of Kiev.

[7] William Humphreys also favors a reconstruction making Yaroslav the son, rather than the step-son, of Anna, by invoking onomastic arguments.

His relations with his father were apparently strained,[12] and grew only worse on the news that Vladimir bequeathed the Kievan throne to his younger son, Boris.

[13] The saga Eymundar þáttr hrings is often interpreted as recounting the story of Boris' assassination by the Varangians in the service of Yaroslav.

[13] Sviatopolk returned in 1018 with Polish troops furnished by his father-in-law, seized Kiev,[13] and pushed Yaroslav back into Novgorod.

[15] One of his first actions as a grand prince was to confer on the loyal Novgorodians, who had helped him to gain the Kievan throne, numerous freedoms and privileges.

Leaving aside the legitimacy of Yaroslav's claims to the Kievan throne and his postulated guilt in the murder of his brothers, Nestor the Chronicler and later Russian historians often presented him as a model of virtue, styling him "the Wise".

In response, another brother, Mstislav of Chernigov, whose distant realm bordered the North Caucasus and the Black Sea, hastened to Kiev.

That led to protests in Sweden because the Swedes wanted to reestablish control over their lost eastern territories and bring in tribute from Kievan Rus', as his father Eric the Victorious had, but after years of war against Norway, Sweden no longer had the power to collect regular tributes from Kievan Rus', according to Heimskringla.

[18] In a successful military raid in 1030, he captured Tartu, Estonia and renamed it Yuryev[19] (named after Yury, Yaroslav's patron saint) and forced the surrounding Ugandi County to pay annual tribute.

[24]To defend his state from the Pechenegs and other nomadic tribes threatening it from the south he constructed a line of forts, composed of Yuriev, Bohuslav, Kaniv, Korsun, and Pereyaslavl.

Some mentioned and other celebrated monuments of his reign such as the Golden Gate of Kiev were destroyed during the Mongol invasion of Rus', but later restored.

Saint Sophia's Cathedral in Kiev houses a fresco representing the whole family: Yaroslav, Irene (as Ingegerd was known in Rus'), their four daughters and six sons.

Subsequent questioning of individuals involved in the research and reinterment of the remains seems to point to the idea that Yaroslav's remains were purposely hidden prior to the German occupation of Ukraine and then either lost completely or stolen and transported to the United States, where many ancient religious artifacts were placed to avoid "mistreatment" by the communists.

[31] Afterwards, one of the producers of The Greatest Ukrainians claimed that Yaroslav had only won because of vote manipulation and that (if that had been prevented) the real first place would have been awarded to Stepan Bandera.

On December 12, 2022, on the Constitution Day of the Russian Federation, a monument to Yaroslav the Wise was unveiled at the site near the Novgorod Technical School.

[33] Yaroslav was at the earliest named a saint by Adam of Bremen in his "Deeds of Bishops of the Hamburg Church" in 1075, but he was not formally canonized.

[citation needed] On 9 March 2004, on his 950th death anniversary he was included in the calendar of saints of the Ukrainian Orthodox Church (Moscow Patriarchate).

[citation needed] On 8 December 2005, Patriarch Alexy II of Moscow added his name to the Menologium as a local saint.

[38] On 3 February 2016, the Council of Bishops of the Russian Orthodox Church held in Moscow established church-wide veneration of Yaroslav as a local saint.