I have a couple of recommendations for you on music history! Most of my examples are about Britain because that is my own area of study.

The Democratic Muse: Folk Music Revival in Scotland by Ailie Munro. This book provides an excellent analysis and introduction of the history of folk music revival in Scotland. The folk revival is a phenomenon which affected many different countries in the mid-20th century, and it's had a big impact on how "Celtic" music is understood as a genre today. By going through the political ideologies behind the evolution of the movement in Scotland, Munro brings out the specific ideas that shaped what was considered "folk music" during this crucial period. There's also a great chapter by Morag MacLeod about how the revival differed in Gaelic language music at a time when the Gaelic language was starting to experience a serious decline.

Songs of Gaelic Scotland by Anne Lorne Gillies. While this book is more focused on presenting the lyrics and tunes of songs, each song comes with a historical context section. The earliest songs in the volume go back to the days of the clan bards in the 17th century, so you can trace the evolution of the Gaelic song tradition over time and across different occupations by going through the book.

Reeling Roosters and Dancing Ducks: Celtic Mouth Music by Heather Sparling. This book looks at a specific genre of Gaelic music known as puirt-à-beul, or mouth music (literally "music out of the mouth"). It involves singing tunes very quickly to accompany dancing. In particular, Sparling focuses on the practice among Gaelic diaspora communities in Canada. If you're interested in how ethnic music survives and changes in diaspora communities, this one is a good one to check out.

Singing the Gospel Along Scotland’s North-East Coast, 1859-2009 by Frances Wilkins. I highly recommend this book about sacred song among fishing communities in Northeast Scotland and the Northern Isles. Wilkins looks at how music intersected with economic, social, and religious changes across a century and a half of Scottish history.

Blackface Minstrelsy in Britain by Michael Pickering. This is a really thought-provoking book about how and why blackface minstrel shows remained popular in England even longer than they did in the United States - well into the 1970s! Pickering looks at how musical performances that romanticized agricultural life in the American South tied into anxieties in Britain about urbanization as well as its fading imperial glory.

Rhythms of Labour: Music at Work in Britain by Marek Korcyznski, Michael Pickering, and Emma Robertson. Really interesting overview of the history of people singing while working in Britain. It covers from the early modern period through the 20th century. So there's a big range of things like singing during agricultural labour in Shakespeare's time, all the way up to singing to the radio in factories.

Selling Songs and Smiles: The Sex Trade in Heian and Kamakura Japan by Janet R. Goodwin. Here's a non-British example! This is an excellent book about the history of singing entertainers in the sex trade in medieval Japan. The asobi were singing prostitutes who entertained Heian nobles while they were on pilgrimages. Goodwin looks at how attitudes towards them varied throughout the medieval period, as well as the emergence of different types of singing female entertainers.

Prof. Julian Johnson's Out of Time: Music and the Making of Modernity (2015) is very good. It takes music from c. 1600 and weaves it in and out of topics such as history, technology, language, and place to create a connection to the present. It also has a great introduction on "Modernity" and what it can mean, particularly through the lens, (or earpiece (?)), of music.