While establishment can take on various meanings from religious oaths to test for beliefs, substantive establishment of a particular church and compulsory attendance and financing of such churches, interestingly, lasted the longest in New England.
Massachusett was the last American state to have a substantially established church until 1833. The Pre-1833 text reads:
Article 3
As the happiness of a people, and the good order and preservation of civil government, essentially depend upon piety, religion and morality; and as these cannot be generally diffused through a community, but by the institution of the public worship of God, and of public instructions in piety, religion and morality: Therefore, to promote their happiness and to secure the good order and preservation of their government, the people of this commonwealth have a right to invest their legislature with power to authorize and require, and the legislature shall, from time to time, authorize and require, the several towns, parishes, precincts, and other bodies politic, or religious societies, to make suitable provision, at their own expense, for the institution of the public worship of God, and for the support and maintenance of public Protestant teachers of piety, religion and morality, in all cases where such provision shall not be made voluntarily.
And the people of this commonwealth have also a right to, and do, invest their legislature with authority to enjoin upon all the subjects an attendance upon the instructions of the public teachers aforesaid, at stated times and seasons, if there be any on whose instructions they can conscientiously and conveniently attend.
Provided, notwithstanding, that the several towns, parishes, precincts, and other bodies politic, or religious societies, shall, at all times, have the exclusive right of electing their public teachers, and of contracting with them for their support and maintenance.
And all moneys paid by the subject to the support of public worship, and of the public teachers aforesaid, shall, if he require it, be uniformly applied to the support of the public teacher or teachers of his own religious sect or denomination, provided there be any on whose instructions he attends; otherwise it may be paid towards the support of the teacher or teachers of the parish or precinct in which the said moneys are raised.
Any every denomination of Christians, demeaning themselves peaceably, and as good subjects of the commonwealth, shall be equally under the protection of the law: and no subordination of any one sect or denomination to another shall ever be established by law.
This article was amended in 1833.
I think there might be something to be said that the essence of Christia America, if not outright lost, was substantially diminished, when New England lost its Protestant establishment.