William I of Berg
William I of Berg( c. 1242 – 16 April 1308) was the son of Count Adolf VII of Berg and of Margaret of Hochstaden.
Upon the death of his brother, Count Adolf VIII of Berg, William succeeded as Count of Berg.
Formerly serving as a monk, he was absolved of his religious vows by the pope in order to take the position.
His tenure was notable due to increased and constant conflict with the Archbishop of Cologne.
In 1300 he supported King Albert I of Germany against the Rhenish electors which further strengthened his position against the archbishop.
During his life he started foundations for monasteries and churches, including those in Beyenburg( now part of Wuppertal) and Gräfrath.
He was also served as the benefactor of the citizens of Hückeswagen.
William married Irmgard of Cleves(? –11 May 1319), widow of Conrad I of Saffenburg and daughter of Dietrich VI, Count of Cleves.
William and Irmgard are buried in the Berg family vault of the Altenberg Cathedral.
As William had no children, his nephew Adolf IX of Berg, son of his brother Henry of Berg, Lord of Windeck succeeded him as Count of Berg.
William VII of Jülich, 1st Duke of Berg
William VII of Jülich, 1st Duke of Berg( – 25 June 1408) was born in Jülich, as the son of Gerhard VI of Jülich, Count of Berg and Ravensberg, and Margaret, daughter and heiress of Otto IV, Count of Ravensberg, and Margaret of Berg.
Upon his father's death in 1360, William became Count of Berg and Ravensberg, a title that his father had gained by marrying the heiress of Berg and Ravensberg.
In 1380, King Wenzel elevated him to the rank of Duke, thus becoming the first Duke of Berg.
William fought the counties of Mark and Cleves to prevent them from combining but in 1397 he was taken prisoner in the battle of Kleverhamm.
He lost Remagen, Kaiserwerth and Sinzig to his nephew Adolf IV, Count of Kleve- Mark and due to these losses, his sons turned against him and imprisoned him in 1403/ 04.
He ultimately forced them to submit and later supported his brother- in- law Rupert, King of Germany against Guelders- Jülich and won the county of Blankenburg.
William died on 25 June 1408 and is buried in the Abteikirche in Altenberg.
Eberhard I, Count of the Mark
Eberhard I( – 1308) was a German nobleman.
He was Count of the Mark from 1277 until his death.
He was the son of Engelbert I, Count of the Mark en Cunigonde of Blieskastel.
In 1277, Count Herman of Lohn abducted Eberhard's father Count Engelbert I, Count of the Mark near Tecklenburg and imprisoned him in the Castle of Bredevoort, where he later died.
In 1278 Eberhard took revenge and conquered the castle.
Eberhard also participated in the alliance against the Electorate of Cologne and gained the independence of the County of Mark from the Archbishop of Cologne after the victory in the Battle of Worringen in 1288.
He also obtained Brakel, Westhofen and Waltrop.
Engelbert I, Count of the Mark
Engelbert I, Count of the Mark( died 16 November 1277 at Castle of Bredevoort) was a German nobleman.
He was the ruling Count of the Mark from 1249 until his death.
Henry, Count of Berg
Henry, Count of Berg, or Heinrich( I) von Berg- Schelklingen( died before 1116) was a count of Berg. Henryk was married to Adelajda of Mochental.
He got three sons( Dypold II, Henryk and Rapot) and three daughters: Rycheza, Zofia and Salomea of Berg.
Adolf IV, Count of Berg
Adolf IV of Berg count of Berg from 1132 until 1160 and of Altena (died after 1161), son of Adolf III of Berg count of Berg and Hövel.
He married (1st)
Adelheid von Arnsberg, a daughter of Heinrich count von Rietberg; then (2nd)
Irmgard  von Schwarzenberg, a daughter of Engelbert von Schwarzenberg.
He built the Schloss Altena, and built Altenberg Abbey (1133) where he enters in 1160.
He has issue from his first marriage:
and from his second marriage:
Engelbert I, Count of Berg
Count Engelbert I of Berg (d. July 1189 in Serbia) ruled the County of Berg from 1160 to 1189.
He was the son of Adolf IV of Berg.
Through his loyalty to the German Emperor and the Archbishops of Cologne
he succeeded in stabilising the county and increasing its revenues.
He took Bensberg Palace, Neu-Windeck and Elberfeld.
In July 1189 he was killed near Kovin, in Serbia, while on his way to the Holy Land with the crusade of emperor Frederick Barbarossa.
He married Margaret of Geldern (born 1157, died 1190?)
and his sons were:
Adolf III of Berg
Adolf III of Berg( 1080 – 12 October 1152) was count of Berg from 1093 until 1132, and count of Hövel from 1090 until 1106, and Vogt of Werden.
He was the son of Adolf II of Berg- Hövel, count of Berg, and Adelaide of Lauffen.
He married Adelheid of Cleves( von Kleve), a daughter of Dietrich II count of Cleves( died 1118).
They had issue:
Irmgard of Berg
Irmgard of Berg, heiress of Berg( died 1248 – 1249), was the child of Adolf VI count of Berg( 1185–1218) and Berta von Sayn.
She married in 1217 Henry IV, Duke of Limburg( since 1226), who became count of Berg in 1225.
Henry IV of Limburg- Berg died on 25 Feb 1246; their descendants were counts of Berg, the county of Berg leaving the descendance of the Ezzonen.
Henry of Berg, Lord of Windeck
Henry of Berg, Lord of Windeck( bef. 1247 – 8 March 1290/ 96) was the son of Adolf VII of Berg and Margaret of Hochstaden.
He was the younger brother of Adolf VIII of Berg and William I of Berg. From 1271- 1281
Henry served as a governor for his brother Adolf who became Count of Berg in 1259.
Henry and his brother Adolf supported John I, Duke of Brabant in his succession war for the Duchy of Limburg, which culminated in the Battle of Worringen in 1288.
Henry resided at Windeck castle, probably as an official of his brother.
Windeck was one of the four main Berg castles, which had come into the possession of Berg by 1247.
Henry is buried with other members of the house of Berg at Altenberg Cathedral.

Question: Who is Engelbert I, Count Of Berg's paternal grandfather?