Blackbirds breed from various Atlantic islands (the Canaries and Azores, north to the Faroes and Iceland) to North Africa, Europe (except for north Fenno-Scandia, north and much of southern Russia), Asia Minor and the Middle East, parts of southern Asia, Sri Lanka and eastern China. They have also been introduced into southern Australia and New Zealand.
    They are one of the commonest birds in Britain, absent only from a few of the highest areas in Scotland and from some remote islands. Though still present, they are thinner on the ground in upland areas of Wales, northern England and Scotland.. National surveys show that numbers in Britain declined by a third between the mid 1970s and the mid 1990s, but this was partially reversed by a  23% increase between 1995 and 2010. The British population is almost entirely sedentary,though a small number migrate to France or Ireland in winter. On the other hand, large numbers from Fenno-Scandia, Germany and the Low Countries move into Britain in autumn, mainly on passage to winter in southwest Europe, though a proportion remain to winter in Britain.
    In Wiltshire they have always been so common that they are taken for granted and receive little coverage in the records except for remarks on out of the ordinary features such as unusual nest sites, early arrivals or abnormal plumage. Birds of Wiltshire recorded them in 909 of the county's 915 tetrads, with breeding in 847 of them. WTA2 found them in 911 tetrads, with breeding in 753.
The following references are used throughout these species’ accounts, in the abbreviated form given in quotation marks:
1968-72 Breeding Atlas” – Sharrack, J.T.R. 1976:  The Atlas of Breeding Birds in Britain and Ireland. T. & A. Poyser
1981-84 Winter Atlas” – Lack, P.C. 1986:  The Atlas of Wintering Birds in Britain and Ireland. T. & A. Poyser
1988-91 Breeding Atlas” – Gibbons, D.W., Reid, J.B. & Chapman, R.A. 1993: The New Atlas of Breeding Birds in Britain and Ireland 1988-91. T. & A. Poyser
Birds of Wiltshire” – Ferguson-Lees, I.J. et al. 2007: Birds of Wiltshire, published by the tetrad atlas group of the Wiltshire Ornithological Society after mapping fieldwork 1995-2000. Wiltshire Ornithological Society.
“Bird Atlas 2007-2011”-– Balmer, D.E., Gillings, S., Caffrey, B.J., Swann, R.L., Downie, I.S. and Fuller, R.J. 2013: The Breeding and Wintering Birds of Britain and Ireland. BTO Books. 
WTA2” – ("Wiltshire Tetrad Atlas 2 ") the present electronic publication, bringing together the Wiltshire data from “Birds of Wiltshire” and “Bird Atlas 2007-11”, together with data from further fieldwork carried out in 2011 and 2012.
"Hobby" - the annual bird report of the Wiltshire Ornithological Society.