Reports of an upmarket Cadillac flagship – something to battle imports like the Mercedes S-Class and BMW 7 Series – have been surfacing for years, intensifying after last year's Elmiraj concept. GM's luxury brand has finally given the official confirmation, announcing plans to begin production on the CT6 flagship by the end of 2015.

Save perhaps for the C7 Corvette, we can't think of another recent GM vehicle subject to more rumors than the Cadillac flagship. When Cadillac's current flagship car, the XTS, debuted as a concept back in 2010, it was understood that the model would likely be a stopgap, sitting at the top of the post-STS/DTS line, but not eye to eye with the German flagships.

Back in 2011, as Cadillac was clearing out the last of the STS/DTS models in preparation for the XTS launch, global marketing director James R. Vurpillat told WardsAuto: "Our priority is to get the main segments covered. Then we can start thinking of cars in the S-Class and 7 Series range. I’d like to have a car like the concept Cadillac Sixteen."

Cadillac has fueled the idea of a super-XTS flagship ever since, showing stylish, top-shelf concept cars like the Ciel and Elmiraj. When introducing those two concepts at respective Concours d'Elegance Pebble Beach events, it used foreshadowing in language like "product ascent," "range-topping flagship" and "top of Cadillac's range." In the absence of any official flagship confirmation, however, only rumor tied those concepts to upcoming products. That is, until this month, when Cadillac confirmed that a flagship sedan is indeed in the works.

"The objective for this upcoming model is to lift the Cadillac range by entering the elite class of top-level luxury cars," said Cadillac president Johan de Nysschen. "Currently in development, this new rear wheel drive-oriented sedan uses completely new, custom-designed materials on a unique vehicle architecture."

With the new model, Cadillac is also launching a new naming structure, leaving the "TS" convention in the past. The new flagship will go by the CT6 moniker, setting a precedent of familiar letters like "CT" to identify the model and a number to show its level within the greater Cadillac lineup.

"As we expand the portfolio, we can assist consumers in placing the cars within a structure, as they compare cars both within our showroom and across the market generally," explains Cadillac chief marketing officer Uwe Ellinghaus. "However, this will be an evolutionary process – we will only change a product’s name when the product itself is redesigned or an all-new model is created, as in this instance."

Cadillac plans to reveal the CT6 in the first half of 2015, putting it into production in the fourth quarter of that year. That timeframe is a bit off for the launch of Super Cruise automated driving, according to the "2017 model year" quoted earlier this month by GM CEO Mary Barra. However, between Barra's admission that Super Cruise would launch on a model in a new segment and Cadillac's description of the CT6 as a "high-technology" car, it seems very likely the CT6 will be the first Super Cruise-equipped model in Cadillac's line.

Whether that means Cadillac will get the tech to market on the 2016 CT6, sooner than Barra announced, or will wait a model year remains to be seen. Or maybe it has a 2017 Ciel-inspired CT6 Roadster in the works?

The car's "high tech" designation also relates to its construction. The CT6's new architecture will incorporate lightweight materials and new construction techniques. Cadillac anticipates the CT6 being the lightest sedan in its class.

Cadillac's busy media department also announced last week that the luxury brand will become its own business unit, opening global headquarters in New York City next year. That move won't affect manufacturing, however, and the CT6 will join the ELR in being produced at GM's Detroit-Hamtramck plant. The plant was recently upgraded with CT6-specific tooling as part of a greater US$384 million investment in the facility.

Given Cadillac's first half of 2015 timeline and the car's built-in-Detroit roots, we'll be looking for this one at next year's North American International Auto Show. Then again, with Cadillac moving operations to the Big Apple, there's the chance we may have to wait until the New York Auto Show a few months later.

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