Bertha was the second illegitimate daughter of Lothair II

Lothair II of Lotharingia

Lothair II was the second son of Emperor Lothair I and Ermengarde of Tours. He was married to Teutberga, daughter of Boso the Elder. He is the namesake of the Lothair Crystal, which he probably commissioned, and of the Cross of Lothair, which was made over a century after his death but...

, King of Lotharingia, by his concubine Waldrada. She was renowned to be beautiful, spirited, and courageous. Ambition, coupled with her influence, involved her husbands in many wars.

She married firstly to Bosonid Theobald of Arles

Theobald of Arles

Theobald, count of Arles, was a Frank from the Bosonid-family. He was son of Hucbert and he married Bertha - an illegitimate daughter of Lothair II, King of Lotharingia - that was renowned for her beauty and spirit. They had two sons Hugh of Italy and Boso of Tuscany. Theobald died in 925....

, by which she had: Boso

Boso of Tuscany

Boso was the count of Arles and Avignon , and margrave of Tuscany . He was the younger son of Theobald of Arles and Bertha, illegitimate daughter of Lothair II of Lotharingia. His elder brother was Hugh, king of Italy.Boso supported his brother's Italian designs...

 and Hugh of Provence

Hugh of Italy

Hugh of Arles was King of Italy from 924 until his death. He was a Bosonid. During his reign, he empowered his relatives at the expense of the aristocracy and tried to establish a relationship with the Byzantine-Roman Empire...

, later king of Italy

King of Italy

King of Italy is a title adopted by many rulers of the Italian peninsula after the fall of the Roman Empire...

. Her second husband was Adalbert II of Tuscany

Adalbert II of Tuscany

Adalbert II , called the Rich, son and successor of Adalbert I of Tuscany, and grandson of Boniface II, was much concerned in the troubles of Lombardy, at a time when so many princes were contending for the wrecks of the Carolingian Empire. Before his father died in 884 or 886, he is accredited the...

 and her two sons, Guy

Guy of Tuscany

Guy was the count and duke of Lucca and margrave of Tuscany from 915, the death of his father Adalbert II, to his own death. He was originally under the regency of his mother Bertha, daughter of Lothair II of Lotharingia, until 916.He kept court at Mantua around the year 920...

 and Lambert

Lambert of Tuscany

Lambert was the second son of Adalbert II of Tuscany and Bertha, daughter of Lothair II of Lotharingia. He succeeded his elder brother, Guy, as count and duke of Lucca and margrave of Tuscany on his death in 928 or 929 without heirs....

, both ruled Tuscany later. Guy's minority was spent under her regency. When Hugh desired to marry Marozia

Marozia

Marozia, born Maria and also known as Mariuccia or Mariozza , was a Roman noblewoman who was the alleged mistress of Pope Sergius III and was given the unprecedented titles senatrix and patricia of Rome by Pope John X.Edward Gibbon wrote of her that the "influence of two sister prostitutes,...

, the widow of his half-brother Guy, he tried to eliminate the descendants of his mother by her second husband.

She also had a daughter Ermengard, who married Adalbert I of Ivrea

Adalbert I of Ivrea

Adalbert I was the son of Anscar of Ivrea and, from his death in 902, margrave of Ivrea.He rebelled against his father-in-law Berengar I in 905 in support of Louis III. When Louis was defeated, captured, and blinded, Adalbert was exiled to Burgundy, whence his family had originated...

.

Bertha is also known for her curious correspondence to Caliph al-Muktafi

Al-Muktafi

Al-Muktafi was the Abbasid Caliph in Baghdad from 902 to 908. He was the son of the previous Caliph, al-Mu'tadid, by a Turkish slave-girl. In command of ar Raqqah at the time of his father's death, he at once returned to the Capital, where he became a favorite of the people for his generosity,...

 in 906, in which she described herself rather grandly as "Queen of the Franks". Bertha's letter is of interest in that she appears to have little knowledge of Baghdad politics or culture, and it is for this reason that details of her correspondence were recorded by one of the Muslim chroniclers. Bertha was seeking a marriage alliance between herself and the Emir of Sicily, unaware that al-Mukfati has little influence over the Aghlabid

Aghlabid

The Aghlabids were a dynasty of emirs, members of the Arab tribe of Bani Tamim, who ruled Ifriqiya, nominally on behalf of the Abbasid Caliph, for about a century, until overthrown by the new power of the Fatimid.-History:...

colony in Sicily. Moreover, the letter was written in a language unfamiliar to the Caliph's translators, and the accompanying gifts (among them a multicoloured woollen coat) which no doubt indicated a largesse on Bertha's part, were unlikely to have impressed al-Muktafi beyond their novelty value.