en.wikipedia.org/wiki/Pope_Benedict_IX

The article dates Benedict IX’s return to the papacy too late.

The Holy See’s official list of pontiffs gives Benedict IX’s second pontificate as beginning on 10 March 1045 and ending on 1 May 1045. It also gives Sylvester III’s pontificate as ending in March 1045, which means Benedict had already resumed the papacy before April began.

A standard reference summary at Encyclopedia.com likewise says Sylvester III’s pontificate lasted only until March 1045 and that Benedict returned after “a little more than one month had elapsed,” again placing Benedict’s restoration before April.

So the article’s statement that Benedict’s forces returned in April 1045 is inconsistent with the official papal chronology and with reference works that place Sylvester’s fall and Benedict’s restoration in March 1045.

The article gives Benedict IX’s Italian name as “Teofilatto di Toscolo.” The place-name Tusculum is rendered in Italian as Tuscolo, not Toscolo.

The Holy See’s Italian page for Benedict IX identifies him as “Teofilatto dei conti di Tuscolo.” Treccani’s entry on Tuscolo likewise uses that spelling throughout and describes Benedict IX as the eleventh-century Teofilatto who became pope in 1032.

So this is not just a stylistic variation: the Italian toponym in the article is misspelled.

This caption cannot be correct as written. It says a grant of Robert II of France was “also signed by Benedict IX.”

But Robert II of France died in 1031. Standard historical reference tables list his reign as 996–1031, and the 1911 Encyclopædia Britannica article on Robert II states that he died at Melun on 20 July 1031.

By contrast, the Holy See’s official list of pontiffs gives Benedict IX’s first pontificate as beginning in August or September 1032. So Benedict IX was not pope until more than a year after Robert II’s death.

That makes the caption’s identification impossible in its present form: a document of Robert II of France could not also have been signed by Pope Benedict IX. The caption likely misidentifies either the king or the document date.

This sentence collapses two events into one and gets the timing of Sylvester III’s election wrong.

The Holy See’s official page for Sylvester III dates his pontificate to 13 or 20 January 1045 – March 1045, not September 1044. A standard reference entry at Encyclopedia.com agrees that Benedict IX was driven from Rome in September 1044, but says that after subsequent infighting John of Sabina was elected pope and that his pontificate ran from January to March 1045.

So it is accurate that Benedict IX was forced out in September 1044, but inaccurate to say Sylvester III was elected then. His recognized pontificate begins only in January 1045.

The infobox gives 20 January 1045 as the end of Benedict IX’s first pontificate, but the official papal chronology places the end earlier.

The Holy See’s page for Benedict IX’s first pontificate dates it from August or September 1032 to September 1044. The Holy See’s page for Sylvester III then begins that pontificate on 13 or 20 January 1045, which means 20 January 1045 is the start of Sylvester III’s pontificate, not the end date of Benedict IX’s first one.

A standard reference entry also says Benedict IX was driven from Rome in September 1044. So the article’s first end date should not be 20 January 1045.