Friedrich Engels was born in Barmen, Rhine Province of the kingdom of Prussia (now a part of Wuppertal in North Rhine-Westphalia, Germany) as the eldest son of a German textile manufacturer, with whom he had a strained relationship.  Due to family circumstances, Engels dropped out of High school and was sent to work as a nonsalaried office clerk at a commercial house in Bremen in 1838.  During this time, Engels began reading the philosophy of Hegel, whose teachings had dominated German philosophy at the time. In September of 1838, he published his first work, a poem titled The Bedouin, in the Bremisches Conversationsblatt No. 40. He also engaged in other literary and journalistic work. In 1841, Engels joined the Prussian Army as a member of the Household Artillery. This position moved him to Berlin where he attended university lectures, began to associate with groups of Young Hegelians and published several articles in the Rheinische Zeitung. Throughout his lifetime, Engels would point out that he was indebted to German philosophy because of its effect on his intellectual development.
Friedrich Engels' house in Primrose Hill
In 1842, the twenty-two year old Engels was sent to Manchester, England to work for the textile firm of Ermen and Engels in which his father was a shareholder. Engels' father thought working in at the Manchester firm might make Engels reconsider the radical leanings that he had developed in high school.On his way to Manchester, Engels visited the office of the Rheinische Zeitung and met Karl Marx for the first time - though the pair did not impress each other.  In Manchester, Engels met Mary Burns, a young woman with whom he began a relationship that lasted until her death in 1862.  Mary acted as a guide through Manchester and helped introduce Engels to the English working class. The two maintained a lifelong relationship; they never married, as Engels was against the institution of marriage which he saw as unnatural and unjust.
During his time in Manchester, Engels took notes and personally observed the horrible working conditions of English workers. These notes and observations, along with his experience working in his father's commercial firm, formed the basis for his first book The Condition of the Working Class in England in 1844. Whilst writing Conditions of the Working Class, Engels continued his involvement with radical journalism and politics. He frequented some members of the English labour & Chartist movements and wrote for several different journals, including The Northern Star, Robert Owen’s New Moral World & the Democratic Review newspaper.
After a productive stay in England, Engels decided to return to Germany in 1844. While traveling back to Germany, he stopped in Paris to meet Karl Marx, with whom he had an earlier correspondence. Marx and Engels met at the Café de la Régence on the Place du Palais, August 28, 1844. The two became close friends and would remain so for their entire lives. Engels ended up staying in Paris in order to help Marx write The Holy Family, which was an attack on the Young Hegelians and the Bauer brothers. Engels' earliest contribution to Marx's work was writing to the Deutsch-französische Jahrbücher journal, which was edited by both Marx and Arnold Ruge in Paris in the same year.
Between 1845 and 1848, Engels and Marx lived in Brussels, spending much of their time organizing the city's German workers. Shortly after their arrival, they contacted and joined the underground German Communist League and were commissioned by the League to write a pamphlet explaining the principles of Communism. This became the The Manifesto of the Communist Party, better known as the Communist Manifesto. It was first published on February 21 1848.